diff --git a/CHANGELOG.md b/CHANGELOG.md
index 1d9176fca4..e3120bcb48 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,6 +2,24 @@
 documentation](doc/development/changelog.md) for instructions on adding your own
 entry.
 
+## 14.2.6 (2021-10-28)
+
+### Security (13 changes)
+
+- [Highlight usage of unicode bidi characters](gitlab-org/security/gitlab@18a768bb3cd19b6dc780bb85d91a93605ec8aa4f) ([merge request](gitlab-org/security/gitlab!1939))
+- [Fix dompurify.js to prevent path traversal attacks](gitlab-org/security/gitlab@cfd7c715162c22060b9b80268ef501a9e604421a) ([merge request](gitlab-org/security/gitlab!1931))
+- [Refresh authorizations on transfer of groups having project shares](gitlab-org/security/gitlab@3fc08eb869156a090b015e78da79c8ced16a7162) ([merge request](gitlab-org/security/gitlab!1918))
+- [Do not allow Applications API to create apps with blank scopes](gitlab-org/security/gitlab@c4ffc8c0ee5356bcb9b76dbfa92517589b4225a8) ([merge request](gitlab-org/security/gitlab!1924))
+- [Don't allow author to resolve discussions when MR is locked via GraphQL](gitlab-org/security/gitlab@fe2d0b6f250b60619da97f162c93c9e645daf4af) ([merge request](gitlab-org/security/gitlab!1921))
+- [Workhorse: Allow uploading only a single file](gitlab-org/security/gitlab@89b04599592b7dfc0e4883cfde5d3ecd9ea855b2) ([merge request](gitlab-org/security/gitlab!1915))
+- [Group owners should see SCIM token only once](gitlab-org/security/gitlab@d52c1e41f38039db075a7a3418b8eb9ed8474c2a) ([merge request](gitlab-org/security/gitlab!1908)) **GitLab Enterprise Edition**
+- [Respect visibility level settings when updating project via API](gitlab-org/security/gitlab@3051d6a00d1a56133a77ecd24313bafb4565d576) ([merge request](gitlab-org/security/gitlab!1905))
+- [Avoid decoding the whole tiff image on isTIFF check](gitlab-org/security/gitlab@bab7f45def8fc81fe4b0961a21b4c90a60358ff9) ([merge request](gitlab-org/security/gitlab!1901))
+- [Adding a '[redacted]' to mask private email addresses](gitlab-org/security/gitlab@8eb9749f40b87b9b49b034bceb263219a4d3b114) ([merge request](gitlab-org/security/gitlab!1895))
+- [Do not display the root password by default](gitlab-org/security/gitlab@4ccf08b6645b9f616657edd266d9d31e3602d170) ([merge request](gitlab-org/security/gitlab!1802))
+- [Set PipelineSchedules to inactive](gitlab-org/security/gitlab@ebee16945325d22ceb5c07b7ba48df6fd0b2f067) ([merge request](gitlab-org/security/gitlab!1878))
+- [Remove external_webhook_token from exported project](gitlab-org/security/gitlab@f3ef12185902f3ed5c9d62ffce07418fd704a753) ([merge request](gitlab-org/security/gitlab!1865))
+
 ## 14.2.5 (2021-09-30)
 
 ### Security (28 changes)
diff --git a/GITALY_SERVER_VERSION b/GITALY_SERVER_VERSION
index 997fcf30e1..d14841bd9a 100644
--- a/GITALY_SERVER_VERSION
+++ b/GITALY_SERVER_VERSION
@@ -1 +1 @@
-14.2.5
\ No newline at end of file
+14.2.6
\ No newline at end of file
diff --git a/VERSION b/VERSION
index 997fcf30e1..d14841bd9a 100644
--- a/VERSION
+++ b/VERSION
@@ -1 +1 @@
-14.2.5
\ No newline at end of file
+14.2.6
\ No newline at end of file
diff --git a/app/assets/javascripts/lib/dompurify.js b/app/assets/javascripts/lib/dompurify.js
index a026f76e51..c375a99724 100644
--- a/app/assets/javascripts/lib/dompurify.js
+++ b/app/assets/javascripts/lib/dompurify.js
@@ -1,5 +1,5 @@
 import { sanitize as dompurifySanitize, addHook } from 'dompurify';
-import { getBaseURL, relativePathToAbsolute } from '~/lib/utils/url_utility';
+import { getNormalizedURL, getBaseURL, relativePathToAbsolute } from '~/lib/utils/url_utility';
 
 const defaultConfig = {
   // Safely allow SVG <use> tags
@@ -11,12 +11,14 @@ const defaultConfig = {
 
 // Only icons urls from `gon` are allowed
 const getAllowedIconUrls = (gon = window.gon) =>
-  [gon.sprite_file_icons, gon.sprite_icons].filter(Boolean);
+  [gon.sprite_file_icons, gon.sprite_icons]
+    .filter(Boolean)
+    .map((path) => relativePathToAbsolute(path, getBaseURL()));
 
-const isUrlAllowed = (url) => getAllowedIconUrls().some((allowedUrl) => url.startsWith(allowedUrl));
+const isUrlAllowed = (url) =>
+  getAllowedIconUrls().some((allowedUrl) => getNormalizedURL(url).startsWith(allowedUrl));
 
-const isHrefSafe = (url) =>
-  isUrlAllowed(url) || isUrlAllowed(relativePathToAbsolute(url, getBaseURL()));
+const isHrefSafe = (url) => url.match(/^#/) || isUrlAllowed(url);
 
 const removeUnsafeHref = (node, attr) => {
   if (!node.hasAttribute(attr)) {
@@ -36,13 +38,14 @@ const removeUnsafeHref = (node, attr) => {
  *   <use href="/assets/icons-xxx.svg#icon_name"></use>
  * </svg>
  *
+ * It validates both href & xlink:href attributes.
+ * Note that `xlink:href` is deprecated, but still in use
+ * https://developer.mozilla.org/en-US/docs/Web/SVG/Attribute/xlink:href
+ *
  * @param {Object} node - Node to sanitize
  */
 const sanitizeSvgIcon = (node) => {
   removeUnsafeHref(node, 'href');
-
-  // Note: `xlink:href` is deprecated, but still in use
-  // https://developer.mozilla.org/en-US/docs/Web/SVG/Attribute/xlink:href
   removeUnsafeHref(node, 'xlink:href');
 };
 
diff --git a/app/assets/javascripts/lib/utils/url_utility.js b/app/assets/javascripts/lib/utils/url_utility.js
index e9772232ea..c10e102292 100644
--- a/app/assets/javascripts/lib/utils/url_utility.js
+++ b/app/assets/javascripts/lib/utils/url_utility.js
@@ -397,6 +397,24 @@ export function isSafeURL(url) {
   }
 }
 
+/**
+ * Returns a normalized url
+ *
+ * https://gitlab.com/foo/../baz => https://gitlab.com/baz
+ *
+ * @param {String} url - URL to be transformed
+ * @param {String?} baseUrl - current base URL
+ * @returns {String}
+ */
+export const getNormalizedURL = (url, baseUrl) => {
+  const base = baseUrl || getBaseURL();
+  try {
+    return new URL(url, base).href;
+  } catch (e) {
+    return '';
+  }
+};
+
 export function getWebSocketProtocol() {
   return window.location.protocol.replace('http', 'ws');
 }
diff --git a/app/assets/javascripts/pages/projects/shared/permissions/components/settings_panel.vue b/app/assets/javascripts/pages/projects/shared/permissions/components/settings_panel.vue
index 261f7af7ef..c53d367ed7 100644
--- a/app/assets/javascripts/pages/projects/shared/permissions/components/settings_panel.vue
+++ b/app/assets/javascripts/pages/projects/shared/permissions/components/settings_panel.vue
@@ -37,6 +37,10 @@ export default {
     securityAndComplianceLabel: s__('ProjectSettings|Security & Compliance'),
     snippetsLabel: s__('ProjectSettings|Snippets'),
     wikiLabel: s__('ProjectSettings|Wiki'),
+    pucWarningLabel: s__('ProjectSettings|Warn about Potentially Unwanted Characters'),
+    pucWarningHelpText: s__(
+      'ProjectSettings|Highlight the usage of hidden unicode characters. These have innocent uses for right-to-left languages, but can also be used in potential exploits.',
+    ),
   },
 
   components: {
@@ -178,6 +182,7 @@ export default {
       securityAndComplianceAccessLevel: featureAccessLevel.PROJECT_MEMBERS,
       operationsAccessLevel: featureAccessLevel.EVERYONE,
       containerRegistryAccessLevel: featureAccessLevel.EVERYONE,
+      warnAboutPotentiallyUnwantedCharacters: true,
       lfsEnabled: true,
       requestAccessEnabled: true,
       highlightChangesClass: false,
@@ -752,5 +757,19 @@ export default {
         }}</template>
       </gl-form-checkbox>
     </project-setting-row>
+    <project-setting-row class="gl-mb-5">
+      <input
+        :value="warnAboutPotentiallyUnwantedCharacters"
+        type="hidden"
+        name="project[project_setting_attributes][warn_about_potentially_unwanted_characters]"
+      />
+      <gl-form-checkbox
+        v-model="warnAboutPotentiallyUnwantedCharacters"
+        name="project[project_setting_attributes][warn_about_potentially_unwanted_characters]"
+      >
+        {{ $options.i18n.pucWarningLabel }}
+        <template #help>{{ $options.i18n.pucWarningHelpText }}</template>
+      </gl-form-checkbox>
+    </project-setting-row>
   </div>
 </template>
diff --git a/app/assets/javascripts/snippets/components/show.vue b/app/assets/javascripts/snippets/components/show.vue
index 46629a569e..35d88d5ec8 100644
--- a/app/assets/javascripts/snippets/components/show.vue
+++ b/app/assets/javascripts/snippets/components/show.vue
@@ -66,7 +66,13 @@ export default {
           data-qa-selector="clone_button"
         />
       </div>
-      <snippet-blob v-for="blob in blobs" :key="blob.path" :snippet="snippet" :blob="blob" />
+      <snippet-blob
+        v-for="blob in blobs"
+        :key="blob.path"
+        :snippet="snippet"
+        :blob="blob"
+        class="project-highlight-puc"
+      />
     </template>
   </div>
 </template>
diff --git a/app/assets/stylesheets/framework/highlight.scss b/app/assets/stylesheets/framework/highlight.scss
index b4a1d9f997..122c605e60 100644
--- a/app/assets/stylesheets/framework/highlight.scss
+++ b/app/assets/stylesheets/framework/highlight.scss
@@ -85,3 +85,9 @@
 td.line-numbers {
   line-height: 1;
 }
+
+.project-highlight-puc .unicode-bidi::before {
+  content: '�';
+  cursor: pointer;
+  text-decoration: underline wavy $red-500;
+}
diff --git a/app/controllers/projects_controller.rb b/app/controllers/projects_controller.rb
index b0e690a74c..a3a0d1e2ca 100644
--- a/app/controllers/projects_controller.rb
+++ b/app/controllers/projects_controller.rb
@@ -398,6 +398,7 @@ class ProjectsController < Projects::ApplicationController
       show_default_award_emojis
       squash_option
       mr_default_target_self
+      warn_about_potentially_unwanted_characters
     ]
   end
 
diff --git a/app/graphql/mutations/issues/set_severity.rb b/app/graphql/mutations/issues/set_severity.rb
index 778563ba05..872a0e7b33 100644
--- a/app/graphql/mutations/issues/set_severity.rb
+++ b/app/graphql/mutations/issues/set_severity.rb
@@ -8,6 +8,8 @@ module Mutations
       argument :severity, Types::IssuableSeverityEnum, required: true,
                description: 'Set the incident severity level.'
 
+      authorize :admin_issue
+
       def resolve(project_path:, iid:, severity:)
         issue = authorized_find!(project_path: project_path, iid: iid)
         project = issue.project
diff --git a/app/helpers/projects_helper.rb b/app/helpers/projects_helper.rb
index f30223f6f1..fc6d675246 100644
--- a/app/helpers/projects_helper.rb
+++ b/app/helpers/projects_helper.rb
@@ -377,6 +377,12 @@ module ProjectsHelper
     }
   end
 
+  def project_classes(project)
+    return "project-highlight-puc" if project.warn_about_potentially_unwanted_characters?
+
+    ""
+  end
+
   private
 
   def tab_ability_map
@@ -533,6 +539,7 @@ module ProjectsHelper
       metricsDashboardAccessLevel: feature.metrics_dashboard_access_level,
       operationsAccessLevel: feature.operations_access_level,
       showDefaultAwardEmojis: project.show_default_award_emojis?,
+      warnAboutPotentiallyUnwantedCharacters: project.warn_about_potentially_unwanted_characters?,
       securityAndComplianceAccessLevel: project.security_and_compliance_access_level,
       containerRegistryAccessLevel: feature.container_registry_access_level
     }
diff --git a/app/models/concerns/resolvable_discussion.rb b/app/models/concerns/resolvable_discussion.rb
index 3e1e5faee5..60e1dde17b 100644
--- a/app/models/concerns/resolvable_discussion.rb
+++ b/app/models/concerns/resolvable_discussion.rb
@@ -81,8 +81,7 @@ module ResolvableDiscussion
     return false unless current_user
     return false unless resolvable?
 
-    current_user == self.noteable.try(:author) ||
-      current_user.can?(:resolve_note, self.project)
+    current_user.can?(:resolve_note, self.noteable)
   end
 
   def resolve!(current_user)
diff --git a/app/models/namespace.rb b/app/models/namespace.rb
index 261639a4ec..1f903eba71 100644
--- a/app/models/namespace.rb
+++ b/app/models/namespace.rb
@@ -26,6 +26,8 @@ class Namespace < ApplicationRecord
   SHARED_RUNNERS_SETTINGS = %w[disabled_and_unoverridable disabled_with_override enabled].freeze
   URL_MAX_LENGTH = 255
 
+  PATH_TRAILING_VIOLATIONS = %w[.git .atom .].freeze
+
   cache_markdown_field :description, pipeline: :description
 
   has_many :projects, dependent: :destroy # rubocop:disable Cop/ActiveRecordDependent
@@ -162,9 +164,14 @@ class Namespace < ApplicationRecord
       # Remove everything that's not in the list of allowed characters.
       path.gsub!(/[^a-zA-Z0-9_\-\.]/,    "")
       # Remove trailing violations ('.atom', '.git', or '.')
-      path.gsub!(/(\.atom|\.git|\.)*\z/, "")
+      loop do
+        orig = path
+        PATH_TRAILING_VIOLATIONS.each { |ext| path = path.chomp(ext) }
+        break if orig == path
+      end
+
       # Remove leading violations ('-')
-      path.gsub!(/\A\-+/,                "")
+      path.gsub!(/\A\-+/, "")
 
       # Users with the great usernames of "." or ".." would end up with a blank username.
       # Work around that by setting their username to "blank", followed by a counter.
diff --git a/app/models/project.rb b/app/models/project.rb
index 81b04e1316..67fc53c5ff 100644
--- a/app/models/project.rb
+++ b/app/models/project.rb
@@ -412,8 +412,8 @@ class Project < ApplicationRecord
     :container_registry_access_level, :container_registry_enabled?,
     to: :project_feature, allow_nil: true
   alias_method :container_registry_enabled, :container_registry_enabled?
-  delegate :show_default_award_emojis, :show_default_award_emojis=,
-    :show_default_award_emojis?,
+  delegate :show_default_award_emojis, :show_default_award_emojis=, :show_default_award_emojis?,
+    :warn_about_potentially_unwanted_characters, :warn_about_potentially_unwanted_characters=, :warn_about_potentially_unwanted_characters?,
     to: :project_setting, allow_nil: true
   delegate :scheduled?, :started?, :in_progress?, :failed?, :finished?,
     prefix: :import, to: :import_state, allow_nil: true
@@ -2669,8 +2669,23 @@ class Project < ApplicationRecord
     ci_cd_settings.group_runners_enabled?
   end
 
+  def visible_group_links(for_user:)
+    user = for_user
+    links = project_group_links_with_preload
+    user.max_member_access_for_group_ids(links.map(&:group_id)) if user && links.any?
+
+    DeclarativePolicy.user_scope do
+      links.select { Ability.allowed?(user, :read_group, _1.group) }
+    end
+  end
+
   private
 
+  # overridden in EE
+  def project_group_links_with_preload
+    project_group_links
+  end
+
   def find_integration(integrations, name)
     integrations.find { _1.to_param == name }
   end
diff --git a/app/models/project_group_link.rb b/app/models/project_group_link.rb
index d704f4c2c8..8394ebe1df 100644
--- a/app/models/project_group_link.rb
+++ b/app/models/project_group_link.rb
@@ -15,6 +15,7 @@ class ProjectGroupLink < ApplicationRecord
   validate :different_group
 
   scope :non_guests, -> { where('group_access > ?', Gitlab::Access::GUEST) }
+  scope :in_group, -> (group_ids) { where(group_id: group_ids) }
 
   alias_method :shared_with_group, :group
 
diff --git a/app/models/user.rb b/app/models/user.rb
index 08b25d7a6f..3eb4035c89 100644
--- a/app/models/user.rb
+++ b/app/models/user.rb
@@ -1459,7 +1459,7 @@ class User < ApplicationRecord
       name: name,
       username: username,
       avatar_url: avatar_url(only_path: false),
-      email: email
+      email: public_email.presence || _('[REDACTED]')
     }
   end
 
diff --git a/app/policies/issuable_policy.rb b/app/policies/issuable_policy.rb
index 61263e47d7..39ce26526e 100644
--- a/app/policies/issuable_policy.rb
+++ b/app/policies/issuable_policy.rb
@@ -11,6 +11,8 @@ class IssuablePolicy < BasePolicy
     @user && @subject.assignee_or_author?(@user)
   end
 
+  condition(:is_author) { @subject&.author == @user }
+
   rule { can?(:guest_access) & assignee_or_author }.policy do
     enable :read_issue
     enable :update_issue
@@ -20,6 +22,10 @@ class IssuablePolicy < BasePolicy
     enable :reopen_merge_request
   end
 
+  rule { is_author }.policy do
+    enable :resolve_note
+  end
+
   rule { locked & ~is_project_member }.policy do
     prevent :create_note
     prevent :admin_note
diff --git a/app/policies/project_policy.rb b/app/policies/project_policy.rb
index 54b11ea604..b40bfbf5a7 100644
--- a/app/policies/project_policy.rb
+++ b/app/policies/project_policy.rb
@@ -221,6 +221,7 @@ class ProjectPolicy < BasePolicy
     enable :set_note_created_at
     enable :set_emails_disabled
     enable :set_show_default_award_emojis
+    enable :set_warn_about_potentially_unwanted_characters
   end
 
   rule { can?(:guest_access) }.policy do
diff --git a/app/services/concerns/update_visibility_level.rb b/app/services/concerns/update_visibility_level.rb
index b7a161f508..4cd14a2fb5 100644
--- a/app/services/concerns/update_visibility_level.rb
+++ b/app/services/concerns/update_visibility_level.rb
@@ -1,13 +1,17 @@
 # frozen_string_literal: true
 
 module UpdateVisibilityLevel
+  # check that user is allowed to set specified visibility_level
   def valid_visibility_level_change?(target, new_visibility)
-    # check that user is allowed to set specified visibility_level
-    if new_visibility && new_visibility.to_i != target.visibility_level
-      unless can?(current_user, :change_visibility_level, target) &&
-          Gitlab::VisibilityLevel.allowed_for?(current_user, new_visibility)
+    return true unless new_visibility
 
-        deny_visibility_level(target, new_visibility)
+    new_visibility_level = Gitlab::VisibilityLevel.level_value(new_visibility)
+
+    if new_visibility_level != target.visibility_level_value
+      unless can?(current_user, :change_visibility_level, target) &&
+          Gitlab::VisibilityLevel.allowed_for?(current_user, new_visibility_level)
+
+        deny_visibility_level(target, new_visibility_level)
         return false
       end
     end
diff --git a/app/services/groups/transfer_service.rb b/app/services/groups/transfer_service.rb
index b7eae06b96..d0aea848af 100644
--- a/app/services/groups/transfer_service.rb
+++ b/app/services/groups/transfer_service.rb
@@ -177,6 +177,14 @@ module Groups
 
       # schedule refreshing projects for all the members of the group
       @group.refresh_members_authorized_projects
+
+      # When a group is transferred, it also affects who gets access to the projects shared to
+      # the subgroups within its hierarchy, so we also schedule jobs that refresh authorizations for all such shared projects.
+      project_group_shares_within_the_hierarchy = ProjectGroupLink.in_group(group.self_and_descendants.select(:id))
+
+      project_group_shares_within_the_hierarchy.find_each do |project_group_link|
+        AuthorizedProjectUpdate::ProjectRecalculateWorker.perform_async(project_group_link.project_id)
+      end
     end
 
     def raise_transfer_error(message)
diff --git a/app/services/groups/update_service.rb b/app/services/groups/update_service.rb
index 1ad43b051b..2d6334251a 100644
--- a/app/services/groups/update_service.rb
+++ b/app/services/groups/update_service.rb
@@ -15,7 +15,7 @@ module Groups
         return false
       end
 
-      return false unless valid_visibility_level_change?(group, params[:visibility_level])
+      return false unless valid_visibility_level_change?(group, group.visibility_attribute_value(params))
 
       return false unless valid_share_with_group_lock_change?
 
@@ -77,7 +77,7 @@ module Groups
     end
 
     def after_update
-      if group.previous_changes.include?(:visibility_level) && group.private?
+      if group.previous_changes.include?(group.visibility_level_field) && group.private?
         # don't enqueue immediately to prevent todos removal in case of a mistake
         TodosDestroyer::GroupPrivateWorker.perform_in(Todo::WAIT_FOR_DELETE, group.id)
       end
diff --git a/app/services/issuable_base_service.rb b/app/services/issuable_base_service.rb
index 0984238517..4532d46ddd 100644
--- a/app/services/issuable_base_service.rb
+++ b/app/services/issuable_base_service.rb
@@ -139,6 +139,7 @@ class IssuableBaseService < ::BaseProjectService
   def filter_severity(issuable)
     severity = params.delete(:severity)
     return unless severity && issuable.supports_severity?
+    return unless can_admin_issuable?(issuable)
 
     severity = IssuableSeverity::DEFAULT unless IssuableSeverity.severities.key?(severity)
     return if severity == issuable.severity
diff --git a/app/services/projects/update_service.rb b/app/services/projects/update_service.rb
index d6e7f165d7..621068febf 100644
--- a/app/services/projects/update_service.rb
+++ b/app/services/projects/update_service.rb
@@ -49,7 +49,7 @@ module Projects
     private
 
     def validate!
-      unless valid_visibility_level_change?(project, params[:visibility_level])
+      unless valid_visibility_level_change?(project, project.visibility_attribute_value(params))
         raise ValidationError, s_('UpdateProject|New visibility level not allowed!')
       end
 
diff --git a/app/views/layouts/project.html.haml b/app/views/layouts/project.html.haml
index 2df502d289..a54e0351d2 100644
--- a/app/views/layouts/project.html.haml
+++ b/app/views/layouts/project.html.haml
@@ -6,6 +6,7 @@
 - display_subscription_banner!
 - display_namespace_storage_limit_alert!
 - @left_sidebar = true
+- @content_class = [@content_class, project_classes(@project)].compact.join(" ")
 
 - content_for :project_javascripts do
   - project = @target_project || @project
diff --git a/config/gitlab.yml.example b/config/gitlab.yml.example
index f7b1c2f756..36eeb7f851 100644
--- a/config/gitlab.yml.example
+++ b/config/gitlab.yml.example
@@ -176,8 +176,10 @@ production: &base
     ## Application settings cache expiry in seconds (default: 60)
     # application_settings_cache_seconds: 60
 
-    ## Print initial root password to stdout during initialization (default: true)
-    # display_initial_root_password: true
+    ## Print initial root password to stdout during initialization (default: false)
+    # WARNING: setting this to true means that the root password will be printed in
+    # plaintext. This can be a security risk.
+    # display_initial_root_password: false
 
   ## Reply by email
   # Allow users to comment on issues and merge requests by replying to notification emails.
diff --git a/config/initializers/1_settings.rb b/config/initializers/1_settings.rb
index e71f1e1b02..6d61755f03 100644
--- a/config/initializers/1_settings.rb
+++ b/config/initializers/1_settings.rb
@@ -217,8 +217,7 @@ Settings.gitlab['no_todos_messages'] ||= YAML.load_file(Rails.root.join('config'
 Settings.gitlab['impersonation_enabled'] ||= true if Settings.gitlab['impersonation_enabled'].nil?
 Settings.gitlab['usage_ping_enabled'] = true if Settings.gitlab['usage_ping_enabled'].nil?
 Settings.gitlab['max_request_duration_seconds'] ||= 57
-
-Settings.gitlab['display_initial_root_password'] = true if Settings.gitlab['display_initial_root_password'].nil?
+Settings.gitlab['display_initial_root_password'] = false if Settings.gitlab['display_initial_root_password'].nil?
 
 Gitlab.ee do
   Settings.gitlab['mirror_max_delay'] ||= 300
diff --git a/db/fixtures/production/002_admin.rb b/db/fixtures/production/002_admin.rb
index b6a6da3a18..b4710bc3e9 100644
--- a/db/fixtures/production/002_admin.rb
+++ b/db/fixtures/production/002_admin.rb
@@ -26,7 +26,7 @@ if user.persisted?
     if ::Settings.gitlab['display_initial_root_password']
       puts "password: #{user_args[:password]}".color(:green)
     else
-      puts "password: *** - You opted not to display initial root password to STDOUT."
+      puts "password: ******".color(:green)
     end
   else
     puts "password: You'll be prompted to create one on your first visit.".color(:green)
diff --git a/db/migrate/20210929144453_add_warn_about_potentially_unwanted_characters_to_project_settings.rb b/db/migrate/20210929144453_add_warn_about_potentially_unwanted_characters_to_project_settings.rb
new file mode 100644
index 0000000000..a2d1ea5779
--- /dev/null
+++ b/db/migrate/20210929144453_add_warn_about_potentially_unwanted_characters_to_project_settings.rb
@@ -0,0 +1,22 @@
+# frozen_string_literal: true
+
+# See https://docs.gitlab.com/ee/development/migration_style_guide.html
+# for more information on how to write migrations for GitLab.
+
+class AddWarnAboutPotentiallyUnwantedCharactersToProjectSettings < ActiveRecord::Migration[6.0]
+  include Gitlab::Database::MigrationHelpers
+
+  DOWNTIME = false
+
+  def up
+    with_lock_retries do
+      add_column :project_settings, :warn_about_potentially_unwanted_characters, :boolean, null: false, default: true
+    end
+  end
+
+  def down
+    with_lock_retries do
+      remove_column :project_settings, :warn_about_potentially_unwanted_characters
+    end
+  end
+end
diff --git a/db/schema_migrations/20210929144453 b/db/schema_migrations/20210929144453
new file mode 100644
index 0000000000..753ea50c27
--- /dev/null
+++ b/db/schema_migrations/20210929144453
@@ -0,0 +1 @@
+0f808c27d19e6a38d4aa31f2dd820fe226681af84e05c4af47213409b2043e5a
\ No newline at end of file
diff --git a/db/structure.sql b/db/structure.sql
index eee73636eb..d4023d06be 100644
--- a/db/structure.sql
+++ b/db/structure.sql
@@ -17302,6 +17302,7 @@ CREATE TABLE project_settings (
     cve_id_request_enabled boolean DEFAULT true NOT NULL,
     mr_default_target_self boolean DEFAULT false NOT NULL,
     previous_default_branch text,
+    warn_about_potentially_unwanted_characters boolean DEFAULT true NOT NULL,
     CONSTRAINT check_3a03e7557a CHECK ((char_length(previous_default_branch) <= 4096)),
     CONSTRAINT check_bde223416c CHECK ((show_default_award_emojis IS NOT NULL))
 );
diff --git a/lib/api/applications.rb b/lib/api/applications.rb
index be482272b2..346bd6ccfe 100644
--- a/lib/api/applications.rb
+++ b/lib/api/applications.rb
@@ -15,7 +15,7 @@ module API
       params do
         requires :name, type: String, desc: 'Application name'
         requires :redirect_uri, type: String, desc: 'Application redirect URI'
-        requires :scopes, type: String, desc: 'Application scopes'
+        requires :scopes, type: String, desc: 'Application scopes', allow_blank: false
 
         optional :confidential, type: Boolean, default: true,
           desc: 'Application will be used where the client secret is confidential'
diff --git a/lib/api/entities/project.rb b/lib/api/entities/project.rb
index 890b42ed8c..e8e6935a28 100644
--- a/lib/api/entities/project.rb
+++ b/lib/api/entities/project.rb
@@ -100,7 +100,9 @@ module API
       expose :build_coverage_regex
       expose :ci_config_path, if: -> (project, options) { Ability.allowed?(options[:current_user], :download_code, project) }
       expose :shared_with_groups do |project, options|
-        SharedGroupWithProject.represent(project.project_group_links, options)
+        user = options[:current_user]
+
+        SharedGroupWithProject.represent(project.visible_group_links(for_user: user), options)
       end
       expose :only_allow_merge_if_pipeline_succeeds
       expose :allow_merge_on_skipped_pipeline
diff --git a/lib/api/helpers/projects_helpers.rb b/lib/api/helpers/projects_helpers.rb
index becd25595a..30edbe9112 100644
--- a/lib/api/helpers/projects_helpers.rb
+++ b/lib/api/helpers/projects_helpers.rb
@@ -39,6 +39,7 @@ module API
 
         optional :emails_disabled, type: Boolean, desc: 'Disable email notifications'
         optional :show_default_award_emojis, type: Boolean, desc: 'Show default award emojis'
+        optional :warn_about_potentially_unwanted_characters, type: Boolean, desc: 'Warn about Potentially Unwanted Characters'
         optional :shared_runners_enabled, type: Boolean, desc: 'Flag indication if shared runners are enabled for that project'
         optional :resolve_outdated_diff_discussions, type: Boolean, desc: 'Automatically resolve merge request diffs discussions on lines changed with a push'
         optional :remove_source_branch_after_merge, type: Boolean, desc: 'Remove the source branch by default after merge'
diff --git a/lib/api/project_import.rb b/lib/api/project_import.rb
index 039f7b4be4..6e9b7fe4ce 100644
--- a/lib/api/project_import.rb
+++ b/lib/api/project_import.rb
@@ -10,6 +10,8 @@ module API
 
     feature_category :importers
 
+    before { authenticate! unless route.settings[:skip_authentication] }
+
     helpers do
       def import_params
         declared_params(include_missing: false)
@@ -110,6 +112,7 @@ module API
         detail 'This feature was introduced in GitLab 10.6.'
         success Entities::ProjectImportStatus
       end
+      route_setting :skip_authentication, true
       get ':id/import' do
         present user_project, with: Entities::ProjectImportStatus
       end
diff --git a/lib/api/projects.rb b/lib/api/projects.rb
index 3ffedd46c3..2ea7248d03 100644
--- a/lib/api/projects.rb
+++ b/lib/api/projects.rb
@@ -423,7 +423,7 @@ module API
         authorize_admin_project
         attrs = declared_params(include_missing: false)
         authorize! :rename_project, user_project if attrs[:name].present?
-        authorize! :change_visibility_level, user_project if attrs[:visibility].present?
+        authorize! :change_visibility_level, user_project if user_project.visibility_attribute_present?(attrs)
 
         attrs = translate_params_for_compatibility(attrs)
         filter_attributes_using_license!(attrs)
diff --git a/lib/gitlab/background_migration/user_mentions/models/group.rb b/lib/gitlab/background_migration/user_mentions/models/group.rb
index a8b4b59b06..310723570c 100644
--- a/lib/gitlab/background_migration/user_mentions/models/group.rb
+++ b/lib/gitlab/background_migration/user_mentions/models/group.rb
@@ -11,6 +11,10 @@ module Gitlab
 
           has_one :saml_provider
 
+          def root_saml_provider
+            root_ancestor.saml_provider
+          end
+
           def self.declarative_policy_class
             "GroupPolicy"
           end
diff --git a/lib/gitlab/import_export/project/import_export.yml b/lib/gitlab/import_export/project/import_export.yml
index eac671a3a0..d0cb362134 100644
--- a/lib/gitlab/import_export/project/import_export.yml
+++ b/lib/gitlab/import_export/project/import_export.yml
@@ -171,9 +171,11 @@ excluded_attributes:
     - :marked_for_deletion_by_user_id
     - :compliance_framework_setting
     - :show_default_award_emojis
+    - :warn_about_potentially_unwanted_characters
     - :services
     - :exported_protected_branches
     - :repository_size_limit
+    - :external_webhook_token
   namespaces:
     - :runners_token
     - :runners_token_encrypted
@@ -377,6 +379,8 @@ excluded_attributes:
   system_note_metadata:
     - :description_version_id
     - :note_id
+  pipeline_schedules:
+    - :active
 methods:
   notes:
     - :type
diff --git a/lib/gitlab/import_export/project/relation_factory.rb b/lib/gitlab/import_export/project/relation_factory.rb
index 102fcedd2f..888a5a10f2 100644
--- a/lib/gitlab/import_export/project/relation_factory.rb
+++ b/lib/gitlab/import_export/project/relation_factory.rb
@@ -84,6 +84,7 @@ module Gitlab
           when :'Ci::Pipeline' then setup_pipeline
           when *BUILD_MODELS then setup_build
           when :issues then setup_issue
+          when :'Ci::PipelineSchedule' then setup_pipeline_schedule
           end
 
           update_project_references
@@ -143,6 +144,10 @@ module Gitlab
           @relation_hash['relative_position'] = compute_relative_position
         end
 
+        def setup_pipeline_schedule
+          @relation_hash['active'] = false
+        end
+
         def compute_relative_position
           return unless max_relative_position
 
diff --git a/lib/gitlab/unicode.rb b/lib/gitlab/unicode.rb
new file mode 100644
index 0000000000..b49c5647da
--- /dev/null
+++ b/lib/gitlab/unicode.rb
@@ -0,0 +1,19 @@
+# frozen_string_literal: true
+
+module Gitlab
+  class Unicode
+    # Regular expression for identifying bidirectional control
+    # characters in UTF-8 strings
+    #
+    # Documentation on how this works:
+    # https://idiosyncratic-ruby.com/41-proper-unicoding.html
+    BIDI_REGEXP = /\p{Bidi Control}/.freeze
+
+    class << self
+      # Warning message used to highlight bidi characters in the GUI
+      def bidi_warning
+        _("Potentially unwanted character detected: Unicode BiDi Control")
+      end
+    end
+  end
+end
diff --git a/lib/gitlab/visibility_level.rb b/lib/gitlab/visibility_level.rb
index 64029d4d3f..d378e558b8 100644
--- a/lib/gitlab/visibility_level.rb
+++ b/lib/gitlab/visibility_level.rb
@@ -155,6 +155,14 @@ module Gitlab
       false
     end
 
+    def visibility_attribute_value(attributes)
+      visibility_level_attributes.each do |attr|
+        return attributes[attr] if attributes.has_key?(attr)
+      end
+
+      nil
+    end
+
     def visibility_level_attributes
       [visibility_level_field, visibility_level_field.to_s,
        :visibility, 'visibility']
diff --git a/lib/rouge/formatters/html_gitlab.rb b/lib/rouge/formatters/html_gitlab.rb
index e0e9677fac..9e76225fc5 100644
--- a/lib/rouge/formatters/html_gitlab.rb
+++ b/lib/rouge/formatters/html_gitlab.rb
@@ -21,12 +21,24 @@ module Rouge
           is_first = false
 
           yield %(<span id="LC#{@line_number}" class="line" lang="#{@tag}">)
-          line.each { |token, value| yield span(token, value.chomp! || value) }
+
+          line.each do |token, value|
+            yield highlight_unicode_control_characters(span(token, value.chomp! || value))
+          end
+
           yield %(</span>)
 
           @line_number += 1
         end
       end
+
+      private
+
+      def highlight_unicode_control_characters(text)
+        text.gsub(Gitlab::Unicode::BIDI_REGEXP) do |char|
+          %(<span class="unicode-bidi has-tooltip" data-toggle="tooltip" title="#{Gitlab::Unicode.bidi_warning}">#{char}</span>)
+        end
+      end
     end
   end
 end
diff --git a/locale/gitlab.pot b/locale/gitlab.pot
index 6b4fa438f8..12924ffedf 100644
--- a/locale/gitlab.pot
+++ b/locale/gitlab.pot
@@ -25164,6 +25164,9 @@ msgstr ""
 msgid "Postman collection file path or URL"
 msgstr ""
 
+msgid "Potentially unwanted character detected: Unicode BiDi Control"
+msgstr ""
+
 msgid "Pre-defined push rules."
 msgstr ""
 
@@ -26253,6 +26256,9 @@ msgstr ""
 msgid "ProjectSettings|Global"
 msgstr ""
 
+msgid "ProjectSettings|Highlight the usage of hidden unicode characters. These have innocent uses for right-to-left languages, but can also be used in potential exploits."
+msgstr ""
+
 msgid "ProjectSettings|Internal"
 msgstr ""
 
@@ -26442,6 +26448,9 @@ msgstr ""
 msgid "ProjectSettings|Visualize the project's performance metrics."
 msgstr ""
 
+msgid "ProjectSettings|Warn about Potentially Unwanted Characters"
+msgstr ""
+
 msgid "ProjectSettings|What are badges?"
 msgstr ""
 
@@ -38764,6 +38773,9 @@ msgstr ""
 msgid "[No reason]"
 msgstr ""
 
+msgid "[REDACTED]"
+msgstr ""
+
 msgid "[Redacted]"
 msgstr ""
 
diff --git a/spec/controllers/projects_controller_spec.rb b/spec/controllers/projects_controller_spec.rb
index 9d07006185..5f3843928d 100644
--- a/spec/controllers/projects_controller_spec.rb
+++ b/spec/controllers/projects_controller_spec.rb
@@ -312,6 +312,34 @@ RSpec.describe ProjectsController do
 
         expect { get_show }.not_to change { Gitlab::GitalyClient.get_request_count }
       end
+
+      describe "PUC highlighting" do
+        render_views
+
+        before do
+          expect(controller).to receive(:find_routable!).and_return(public_project)
+        end
+
+        context "option is enabled" do
+          it "adds the highlighting class" do
+            expect(public_project).to receive(:warn_about_potentially_unwanted_characters?).and_return(true)
+
+            get_show
+
+            expect(response.body).to have_css(".project-highlight-puc")
+          end
+        end
+
+        context "option is disabled" do
+          it "doesn't add the highlighting class" do
+            expect(public_project).to receive(:warn_about_potentially_unwanted_characters?).and_return(false)
+
+            get_show
+
+            expect(response.body).not_to have_css(".project-highlight-puc")
+          end
+        end
+      end
     end
 
     context "when the url contains .atom" do
diff --git a/spec/factories/users.rb b/spec/factories/users.rb
index 476c57f2d8..1907d7236e 100644
--- a/spec/factories/users.rb
+++ b/spec/factories/users.rb
@@ -19,6 +19,10 @@ FactoryBot.define do
       admin { true }
     end
 
+    trait :public_email do
+      public_email { email }
+    end
+
     trait :blocked do
       after(:build) { |user, _| user.block! }
     end
diff --git a/spec/frontend/lib/dompurify_spec.js b/spec/frontend/lib/dompurify_spec.js
index fa8dbb12a0..f3ccc13e85 100644
--- a/spec/frontend/lib/dompurify_spec.js
+++ b/spec/frontend/lib/dompurify_spec.js
@@ -22,12 +22,16 @@ const safeUrls = {
 const unsafeUrls = [
   '/an/evil/url',
   '../../../evil/url',
-  'https://evil.url/assets/icons-123a.svg',
+  'https://evil.url/assets/icons-123a.svg#test',
   'https://evil.url/assets/icons-456b.svg',
   `https://evil.url/${rootGon.sprite_icons}`,
   `https://evil.url/${rootGon.sprite_file_icons}`,
   `https://evil.url/${absoluteGon.sprite_icons}`,
   `https://evil.url/${absoluteGon.sprite_file_icons}`,
+  `${rootGon.sprite_icons}/../evil/path`,
+  `${rootGon.sprite_file_icons}/../../evil/path`,
+  `${absoluteGon.sprite_icons}/../evil/path`,
+  `${absoluteGon.sprite_file_icons}/../../https://evil.url`,
 ];
 
 const forbiddenDataAttrs = ['data-remote', 'data-url', 'data-type', 'data-method'];
diff --git a/spec/frontend/lib/utils/url_utility_spec.js b/spec/frontend/lib/utils/url_utility_spec.js
index c8ac7ffc9d..24874804dd 100644
--- a/spec/frontend/lib/utils/url_utility_spec.js
+++ b/spec/frontend/lib/utils/url_utility_spec.js
@@ -607,6 +607,27 @@ describe('URL utility', () => {
     });
   });
 
+  describe('getNormalizedURL', () => {
+    it.each`
+      url                       | base                                 | result
+      ${'./foo'}                | ${''}                                | ${'http://test.host/foo'}
+      ${'../john.md'}           | ${''}                                | ${'http://test.host/john.md'}
+      ${'/images/img.png'}      | ${'https://gitlab.com'}              | ${'https://gitlab.com/images/img.png'}
+      ${'/images/../img.png'}   | ${'https://gitlab.com'}              | ${'https://gitlab.com/img.png'}
+      ${'/images/./img.png'}    | ${'https://gitlab.com'}              | ${'https://gitlab.com/images/img.png'}
+      ${'./images/img.png'}     | ${'https://gitlab.com/user/project'} | ${'https://gitlab.com/user/images/img.png'}
+      ${'../images/../img.png'} | ${'https://gitlab.com/user/project'} | ${'https://gitlab.com/img.png'}
+      ${'/images/img.png'}      | ${'https://gitlab.com/user/project'} | ${'https://gitlab.com/images/img.png'}
+      ${'/images/../img.png'}   | ${'https://gitlab.com/user/project'} | ${'https://gitlab.com/img.png'}
+      ${'/images/./img.png'}    | ${'https://gitlab.com/user/project'} | ${'https://gitlab.com/images/img.png'}
+    `(
+      'converts url "$url" with base "$base" to normalized url => "expected"',
+      ({ url, base, result }) => {
+        expect(urlUtils.getNormalizedURL(url, base)).toBe(result);
+      },
+    );
+  });
+
   describe('getWebSocketProtocol', () => {
     it.each`
       protocol    | expectation
diff --git a/spec/frontend/pages/projects/shared/permissions/components/settings_panel_spec.js b/spec/frontend/pages/projects/shared/permissions/components/settings_panel_spec.js
index 1e562419f3..0020269e4e 100644
--- a/spec/frontend/pages/projects/shared/permissions/components/settings_panel_spec.js
+++ b/spec/frontend/pages/projects/shared/permissions/components/settings_panel_spec.js
@@ -27,6 +27,7 @@ const defaultProps = {
     emailsDisabled: false,
     packagesEnabled: true,
     showDefaultAwardEmojis: true,
+    warnAboutPotentiallyUnwantedCharacters: true,
   },
   isGitlabCom: true,
   canDisableEmails: true,
@@ -97,6 +98,10 @@ describe('Settings Panel', () => {
   const findEmailSettings = () => wrapper.find({ ref: 'email-settings' });
   const findShowDefaultAwardEmojis = () =>
     wrapper.find('input[name="project[project_setting_attributes][show_default_award_emojis]"]');
+  const findWarnAboutPuc = () =>
+    wrapper.find(
+      'input[name="project[project_setting_attributes][warn_about_potentially_unwanted_characters]"]',
+    );
   const findMetricsVisibilitySettings = () => wrapper.find({ ref: 'metrics-visibility-settings' });
   const findOperationsSettings = () => wrapper.find({ ref: 'operations-settings' });
 
@@ -539,6 +544,14 @@ describe('Settings Panel', () => {
     });
   });
 
+  describe('Warn about potentially unwanted characters', () => {
+    it('should have a "Warn about Potentially Unwanted Characters" input', () => {
+      wrapper = mountComponent();
+
+      expect(findWarnAboutPuc().exists()).toBe(true);
+    });
+  });
+
   describe('Metrics dashboard', () => {
     it('should show the metrics dashboard access toggle', () => {
       wrapper = mountComponent();
diff --git a/spec/graphql/mutations/discussions/toggle_resolve_spec.rb b/spec/graphql/mutations/discussions/toggle_resolve_spec.rb
index b03c6cb094..8c11279a80 100644
--- a/spec/graphql/mutations/discussions/toggle_resolve_spec.rb
+++ b/spec/graphql/mutations/discussions/toggle_resolve_spec.rb
@@ -7,6 +7,7 @@ RSpec.describe Mutations::Discussions::ToggleResolve do
     described_class.new(object: nil, context: { current_user: user }, field: nil)
   end
 
+  let_it_be(:author) { create(:user) }
   let_it_be(:project) { create(:project, :repository) }
 
   describe '#resolve' do
@@ -136,20 +137,37 @@ RSpec.describe Mutations::Discussions::ToggleResolve do
           end
         end
       end
+
+      context 'when user is the author and discussion is locked' do
+        let(:user) { author }
+
+        before do
+          issuable.update!(discussion_locked: true)
+        end
+
+        it 'raises an error' do
+          expect { mutation.resolve(id: id_arg, resolve: resolve_arg) }.to raise_error(
+            Gitlab::Graphql::Errors::ResourceNotAvailable,
+            "The resource that you are attempting to access does not exist or you don't have permission to perform this action"
+          )
+        end
+      end
     end
 
     context 'when discussion is on a merge request' do
-      let_it_be(:noteable) { create(:merge_request, source_project: project) }
+      let_it_be(:noteable) { create(:merge_request, source_project: project, author: author) }
 
       let(:discussion) { create(:diff_note_on_merge_request, noteable: noteable, project: project).to_discussion }
+      let(:issuable) { noteable }
 
       it_behaves_like 'a working resolve method'
     end
 
     context 'when discussion is on a design' do
-      let_it_be(:noteable) { create(:design, :with_file, issue: create(:issue, project: project)) }
+      let_it_be(:noteable) { create(:design, :with_file, issue: create(:issue, project: project, author: author)) }
 
       let(:discussion) { create(:diff_note_on_design, noteable: noteable, project: project).to_discussion }
+      let(:issuable) { noteable.issue }
 
       it_behaves_like 'a working resolve method'
     end
diff --git a/spec/graphql/mutations/issues/set_severity_spec.rb b/spec/graphql/mutations/issues/set_severity_spec.rb
index 7ce9c7f662..84736fe7ee 100644
--- a/spec/graphql/mutations/issues/set_severity_spec.rb
+++ b/spec/graphql/mutations/issues/set_severity_spec.rb
@@ -3,26 +3,58 @@
 require 'spec_helper'
 
 RSpec.describe Mutations::Issues::SetSeverity do
-  let_it_be(:user) { create(:user) }
-  let_it_be(:issue) { create(:incident) }
+  let_it_be(:project) { create(:project) }
+  let_it_be(:guest) { create(:user) }
+  let_it_be(:reporter) { create(:user) }
+  let_it_be(:issue) { create(:incident, project: project) }
 
   let(:mutation) { described_class.new(object: nil, context: { current_user: user }, field: nil) }
 
-  specify { expect(described_class).to require_graphql_authorizations(:update_issue) }
+  specify { expect(described_class).to require_graphql_authorizations(:update_issue, :admin_issue) }
+
+  before_all do
+    project.add_guest(guest)
+    project.add_reporter(reporter)
+  end
 
   describe '#resolve' do
     let(:severity) { 'critical' }
-    let(:mutated_incident) { subject[:issue] }
 
-    subject(:resolve) { mutation.resolve(project_path: issue.project.full_path, iid: issue.iid, severity: severity) }
+    subject(:resolve) do
+      mutation.resolve(
+        project_path: issue.project.full_path,
+        iid: issue.iid,
+        severity: severity
+      )
+    end
 
-    it_behaves_like 'permission level for issue mutation is correctly verified'
+    context 'as guest' do
+      let(:user) { guest }
 
-    context 'when the user can update the issue' do
-      before do
-        issue.project.add_developer(user)
+      it 'raises an error' do
+        expect { subject }.to raise_error(Gitlab::Graphql::Errors::ResourceNotAvailable)
       end
 
+      context 'and also author' do
+        let!(:issue) { create(:incident, project: project, author: user) }
+
+        it 'raises an error' do
+          expect { subject }.to raise_error(Gitlab::Graphql::Errors::ResourceNotAvailable)
+        end
+      end
+
+      context 'and also assignee' do
+        let!(:issue) { create(:incident, project: project, assignee_ids: [user.id]) }
+
+        it 'raises an error' do
+          expect { subject }.to raise_error(Gitlab::Graphql::Errors::ResourceNotAvailable)
+        end
+      end
+    end
+
+    context 'as reporter' do
+      let(:user) { reporter }
+
       context 'when issue type is incident' do
         context 'when severity has a correct value' do
           it 'updates severity' do
@@ -48,9 +80,9 @@ RSpec.describe Mutations::Issues::SetSeverity do
       end
 
       context 'when issue type is not incident' do
-        let!(:issue) { create(:issue) }
+        let!(:issue) { create(:issue, project: project) }
 
-        it 'does not updates the issue' do
+        it 'does not update the issue' do
           expect { resolve }.not_to change { issue.updated_at }
         end
       end
diff --git a/spec/helpers/projects_helper_spec.rb b/spec/helpers/projects_helper_spec.rb
index 4dac4403f7..a519b10fe8 100644
--- a/spec/helpers/projects_helper_spec.rb
+++ b/spec/helpers/projects_helper_spec.rb
@@ -953,4 +953,26 @@ RSpec.describe ProjectsHelper do
       )
     end
   end
+
+  describe '#project_classes' do
+    subject { helper.project_classes(project) }
+
+    it { is_expected.to be_a(String) }
+
+    context 'PUC highlighting enabled' do
+      before do
+        project.warn_about_potentially_unwanted_characters = true
+      end
+
+      it { is_expected.to include('project-highlight-puc') }
+    end
+
+    context 'PUC highlighting disabled' do
+      before do
+        project.warn_about_potentially_unwanted_characters = false
+      end
+
+      it { is_expected.not_to include('project-highlight-puc') }
+    end
+  end
 end
diff --git a/spec/lib/api/entities/project_spec.rb b/spec/lib/api/entities/project_spec.rb
new file mode 100644
index 0000000000..8d1c3aa878
--- /dev/null
+++ b/spec/lib/api/entities/project_spec.rb
@@ -0,0 +1,39 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe ::API::Entities::Project do
+  let(:project) { create(:project, :public) }
+  let(:current_user) { create(:user) }
+  let(:options) { { current_user: current_user } }
+
+  let(:entity) do
+    ::API::Entities::Project.new(project, options)
+  end
+
+  subject(:json) { entity.as_json }
+
+  describe '.shared_with_groups' do
+    let(:group) { create(:group, :private) }
+
+    before do
+      project.project_group_links.create!(group: group)
+    end
+
+    context 'when the current user does not have access to the group' do
+      it 'is empty' do
+        expect(json[:shared_with_groups]).to be_empty
+      end
+    end
+
+    context 'when the current user has access to the group' do
+      before do
+        group.add_guest(current_user)
+      end
+
+      it 'contains information about the shared group' do
+        expect(json[:shared_with_groups]).to contain_exactly(include(group_id: group.id))
+      end
+    end
+  end
+end
diff --git a/spec/lib/gitlab/data_builder/build_spec.rb b/spec/lib/gitlab/data_builder/build_spec.rb
index 325fdb9092..9cee0802e8 100644
--- a/spec/lib/gitlab/data_builder/build_spec.rb
+++ b/spec/lib/gitlab/data_builder/build_spec.rb
@@ -5,7 +5,7 @@ require 'spec_helper'
 RSpec.describe Gitlab::DataBuilder::Build do
   let!(:tag_names) { %w(tag-1 tag-2) }
   let(:runner) { create(:ci_runner, :instance, tag_list: tag_names.map { |n| ActsAsTaggableOn::Tag.create!(name: n)}) }
-  let(:user) { create(:user) }
+  let(:user) { create(:user, :public_email) }
   let(:build) { create(:ci_build, :running, runner: runner, user: user) }
 
   describe '.build' do
diff --git a/spec/lib/gitlab/data_builder/pipeline_spec.rb b/spec/lib/gitlab/data_builder/pipeline_spec.rb
index 0e574c7aa8..8b57da8e60 100644
--- a/spec/lib/gitlab/data_builder/pipeline_spec.rb
+++ b/spec/lib/gitlab/data_builder/pipeline_spec.rb
@@ -3,7 +3,7 @@
 require 'spec_helper'
 
 RSpec.describe Gitlab::DataBuilder::Pipeline do
-  let_it_be(:user) { create(:user) }
+  let_it_be(:user) { create(:user, :public_email) }
   let_it_be(:project) { create(:project, :repository) }
 
   let_it_be_with_reload(:pipeline) do
@@ -46,7 +46,7 @@ RSpec.describe Gitlab::DataBuilder::Pipeline do
         name: user.name,
         username: user.username,
         avatar_url: user.avatar_url(only_path: false),
-        email: user.email
+        email: user.public_email
         })
     end
 
diff --git a/spec/lib/gitlab/import_export/project/relation_factory_spec.rb b/spec/lib/gitlab/import_export/project/relation_factory_spec.rb
index 88bd71d3d6..49df231392 100644
--- a/spec/lib/gitlab/import_export/project/relation_factory_spec.rb
+++ b/spec/lib/gitlab/import_export/project/relation_factory_spec.rb
@@ -267,6 +267,35 @@ RSpec.describe Gitlab::ImportExport::Project::RelationFactory, :use_clean_rails_
     end
   end
 
+  context 'pipeline_schedule' do
+    let(:relation_sym) { :pipeline_schedules }
+    let(:relation_hash) do
+      {
+        "id": 3,
+        "created_at": "2016-07-22T08:55:44.161Z",
+        "updated_at": "2016-07-22T08:55:44.161Z",
+        "description": "pipeline schedule",
+        "ref": "main",
+        "cron": "0 4 * * 0",
+        "cron_timezone": "UTC",
+        "active": value,
+        "project_id": project.id
+      }
+    end
+
+    subject { created_object.active }
+
+    [true, false].each do |v|
+      context "when relation_hash has active set to #{v}" do
+        let(:value) { v }
+
+        it "the created object is not active" do
+          expect(created_object.active).to eq(false)
+        end
+      end
+    end
+  end
+
   # `project_id`, `described_class.USER_REFERENCES`, noteable_id, target_id, and some project IDs are already
   # re-assigned by described_class.
   context 'Potentially hazardous foreign keys' do
diff --git a/spec/lib/gitlab/import_export/project/tree_restorer_spec.rb b/spec/lib/gitlab/import_export/project/tree_restorer_spec.rb
index 518a933782..f512f49764 100644
--- a/spec/lib/gitlab/import_export/project/tree_restorer_spec.rb
+++ b/spec/lib/gitlab/import_export/project/tree_restorer_spec.rb
@@ -376,7 +376,7 @@ RSpec.describe Gitlab::ImportExport::Project::TreeRestorer do
             expect(pipeline_schedule.ref).to eq('master')
             expect(pipeline_schedule.cron).to eq('0 4 * * 0')
             expect(pipeline_schedule.cron_timezone).to eq('UTC')
-            expect(pipeline_schedule.active).to eq(true)
+            expect(pipeline_schedule.active).to eq(false)
           end
         end
 
diff --git a/spec/lib/gitlab/import_export/safe_model_attributes.yml b/spec/lib/gitlab/import_export/safe_model_attributes.yml
index b238a4733e..e555886657 100644
--- a/spec/lib/gitlab/import_export/safe_model_attributes.yml
+++ b/spec/lib/gitlab/import_export/safe_model_attributes.yml
@@ -555,7 +555,6 @@ Project:
 - merge_requests_rebase_enabled
 - jobs_cache_index
 - external_authorization_classification_label
-- external_webhook_token
 - pages_https_only
 - merge_requests_disable_committers_approval
 - require_password_to_approve
diff --git a/spec/lib/gitlab/unicode_spec.rb b/spec/lib/gitlab/unicode_spec.rb
new file mode 100644
index 0000000000..68f3266ecc
--- /dev/null
+++ b/spec/lib/gitlab/unicode_spec.rb
@@ -0,0 +1,33 @@
+# frozen_string_literal: true
+
+require "spec_helper"
+
+RSpec.describe Gitlab::Unicode do
+  describe described_class::BIDI_REGEXP do
+    using RSpec::Parameterized::TableSyntax
+
+    where(:bidi_string, :match) do
+      "\u2066"       | true # left-to-right isolate
+      "\u2067"       | true # right-to-left isolate
+      "\u2068"       | true # first strong isolate
+      "\u2069"       | true # pop directional isolate
+      "\u202a"       | true # left-to-right embedding
+      "\u202b"       | true # right-to-left embedding
+      "\u202c"       | true # pop directional formatting
+      "\u202d"       | true # left-to-right override
+      "\u202e"       | true # right-to-left override
+      "\u2066foobar" | true
+      ""             | false
+      "foo"          | false
+      "\u2713"       | false # checkmark
+    end
+
+    with_them do
+      let(:utf8_string) { bidi_string.encode("utf-8") }
+
+      it "matches only the bidi characters" do
+        expect(utf8_string.match?(subject)).to eq(match)
+      end
+    end
+  end
+end
diff --git a/spec/lib/rouge/formatters/html_gitlab_spec.rb b/spec/lib/rouge/formatters/html_gitlab_spec.rb
index d45c8c2a8c..6fa0ac1c4b 100644
--- a/spec/lib/rouge/formatters/html_gitlab_spec.rb
+++ b/spec/lib/rouge/formatters/html_gitlab_spec.rb
@@ -36,5 +36,26 @@ RSpec.describe Rouge::Formatters::HTMLGitlab do
         is_expected.to eq(code)
       end
     end
+
+    context 'when unicode control characters are used' do
+      let(:lang) { 'javascript' }
+      let(:tokens) { lexer.lex(code, continue: false) }
+      let(:code) do
+        <<~JS
+          #!/usr/bin/env node
+
+          var accessLevel = "user";
+          if (accessLevel != "user‮ ⁦// Check if admin⁩ ⁦") {
+              console.log("You are an admin.");
+          }
+        JS
+      end
+
+      it 'highlights the control characters' do
+        message = "Potentially unwanted character detected: Unicode BiDi Control"
+
+        is_expected.to include(%{<span class="unicode-bidi has-tooltip" data-toggle="tooltip" title="#{message}">}).exactly(4).times
+      end
+    end
   end
 end
diff --git a/spec/models/ci/pipeline_spec.rb b/spec/models/ci/pipeline_spec.rb
index da89eccc3b..3ddf7370fe 100644
--- a/spec/models/ci/pipeline_spec.rb
+++ b/spec/models/ci/pipeline_spec.rb
@@ -7,7 +7,7 @@ RSpec.describe Ci::Pipeline, :mailer, factory_default: :keep do
   include StubRequests
   include Ci::SourcePipelineHelpers
 
-  let_it_be(:user) { create(:user) }
+  let_it_be(:user) { create(:user, :public_email) }
   let_it_be(:namespace) { create_default(:namespace).freeze }
   let_it_be(:project) { create_default(:project, :repository).freeze }
 
diff --git a/spec/models/concerns/resolvable_discussion_spec.rb b/spec/models/concerns/resolvable_discussion_spec.rb
index c0e5ddc23b..fc154738f1 100644
--- a/spec/models/concerns/resolvable_discussion_spec.rb
+++ b/spec/models/concerns/resolvable_discussion_spec.rb
@@ -188,6 +188,16 @@ RSpec.describe Discussion, ResolvableDiscussion do
           it "returns true" do
             expect(subject.can_resolve?(current_user)).to be true
           end
+
+          context 'when noteable is locked' do
+            before do
+              allow(subject.noteable).to receive(:discussion_locked?).and_return(true)
+            end
+
+            it 'returns false' do
+              expect(subject.can_resolve?(current_user)).to be_falsey
+            end
+          end
         end
 
         context "when the signed in user can push to the project" do
@@ -200,8 +210,11 @@ RSpec.describe Discussion, ResolvableDiscussion do
           end
 
           context "when the noteable has no author" do
+            before do
+              subject.noteable.author = nil
+            end
+
             it "returns true" do
-              expect(noteable).to receive(:author).and_return(nil)
               expect(subject.can_resolve?(current_user)).to be true
             end
           end
@@ -213,8 +226,11 @@ RSpec.describe Discussion, ResolvableDiscussion do
           end
 
           context "when the noteable has no author" do
+            before do
+              subject.noteable.author = nil
+            end
+
             it "returns false" do
-              expect(noteable).to receive(:author).and_return(nil)
               expect(subject.can_resolve?(current_user)).to be false
             end
           end
diff --git a/spec/models/project_spec.rb b/spec/models/project_spec.rb
index d8f3a63d22..15b751ebe8 100644
--- a/spec/models/project_spec.rb
+++ b/spec/models/project_spec.rb
@@ -660,6 +660,19 @@ RSpec.describe Project, factory_default: :keep do
     it { is_expected.to delegate_method(:container_registry_enabled?).to(:project_feature) }
     it { is_expected.to delegate_method(:container_registry_access_level).to(:project_feature) }
 
+    describe 'project settings' do
+      %i(
+        show_default_award_emojis
+        show_default_award_emojis=
+        show_default_award_emojis?
+        warn_about_potentially_unwanted_characters
+        warn_about_potentially_unwanted_characters=
+        warn_about_potentially_unwanted_characters?
+      ).each do |method|
+        it { is_expected.to delegate_method(method).to(:project_setting).with_arguments(allow_nil: true) }
+      end
+    end
+
     include_examples 'ci_cd_settings delegation' do
       # Skip attributes defined in EE code
       let(:exclude_attributes) do
diff --git a/spec/models/user_spec.rb b/spec/models/user_spec.rb
index 714cb24f27..448bcde01d 100644
--- a/spec/models/user_spec.rb
+++ b/spec/models/user_spec.rb
@@ -5511,16 +5511,29 @@ RSpec.describe User do
   end
 
   describe '#hook_attrs' do
-    it 'includes id, name, username, avatar_url, and email' do
-      user = create(:user)
-      user_attributes = {
+    let(:user) { create(:user) }
+    let(:user_attributes) do
+      {
         id: user.id,
         name: user.name,
         username: user.username,
-        avatar_url: user.avatar_url(only_path: false),
-        email: user.email
+        avatar_url: user.avatar_url(only_path: false)
       }
-      expect(user.hook_attrs).to eq(user_attributes)
+    end
+
+    context 'with a public email' do
+      it 'includes id, name, username, avatar_url, and email' do
+        user.public_email = "hello@hello.com"
+        user_attributes[:email] = user.public_email
+        expect(user.hook_attrs).to eq(user_attributes)
+      end
+    end
+
+    context 'without a public email' do
+      it "does not include email if user's email is private" do
+        user_attributes[:email] = "[REDACTED]"
+        expect(user.hook_attrs).to eq(user_attributes)
+      end
     end
   end
 
diff --git a/spec/policies/issuable_policy_spec.rb b/spec/policies/issuable_policy_spec.rb
index 86b04ccda5..eeb298e853 100644
--- a/spec/policies/issuable_policy_spec.rb
+++ b/spec/policies/issuable_policy_spec.rb
@@ -13,6 +13,10 @@ RSpec.describe IssuablePolicy, models: true do
       let(:merge_request) { create(:merge_request, source_project: project, author: user) }
       let(:policies) { described_class.new(user, merge_request) }
 
+      it 'allows resolving notes' do
+        expect(policies).to be_allowed(:resolve_note)
+      end
+
       context 'when user is able to read project' do
         it 'enables user to read and update issuables' do
           expect(policies).to be_allowed(:read_issue, :update_issue, :reopen_issue, :read_merge_request, :update_merge_request, :reopen_merge_request)
@@ -43,16 +47,24 @@ RSpec.describe IssuablePolicy, models: true do
         it 'can not create a note nor award emojis' do
           expect(policies).to be_disallowed(:create_note, :award_emoji)
         end
+
+        it 'does not allow resolving note' do
+          expect(policies).to be_disallowed(:resolve_note)
+        end
       end
 
       context 'when the user is a project member' do
         before do
-          project.add_guest(user)
+          project.add_developer(user)
         end
 
         it 'can create a note and award emojis' do
           expect(policies).to be_allowed(:create_note, :award_emoji)
         end
+
+        it 'allows resolving notes' do
+          expect(policies).to be_allowed(:resolve_note)
+        end
       end
     end
   end
diff --git a/spec/requests/api/applications_spec.rb b/spec/requests/api/applications_spec.rb
index 959e68e6a0..022451553e 100644
--- a/spec/requests/api/applications_spec.rb
+++ b/spec/requests/api/applications_spec.rb
@@ -5,13 +5,14 @@ require 'spec_helper'
 RSpec.describe API::Applications, :api do
   let(:admin_user) { create(:user, admin: true) }
   let(:user) { create(:user, admin: false) }
-  let!(:application) { create(:application, name: 'another_application', owner: nil, redirect_uri: 'http://other_application.url', scopes: '') }
+  let(:scopes) { 'api' }
+  let!(:application) { create(:application, name: 'another_application', owner: nil, redirect_uri: 'http://other_application.url', scopes: scopes) }
 
   describe 'POST /applications' do
     context 'authenticated and authorized user' do
       it 'creates and returns an OAuth application' do
         expect do
-          post api('/applications', admin_user), params: { name: 'application_name', redirect_uri: 'http://application.url', scopes: '' }
+          post api('/applications', admin_user), params: { name: 'application_name', redirect_uri: 'http://application.url', scopes: scopes }
         end.to change { Doorkeeper::Application.count }.by 1
 
         application = Doorkeeper::Application.find_by(name: 'application_name', redirect_uri: 'http://application.url')
@@ -22,11 +23,12 @@ RSpec.describe API::Applications, :api do
         expect(json_response['secret']).to eq application.secret
         expect(json_response['callback_url']).to eq application.redirect_uri
         expect(json_response['confidential']).to eq application.confidential
+        expect(application.scopes.to_s).to eq('api')
       end
 
       it 'does not allow creating an application with the wrong redirect_uri format' do
         expect do
-          post api('/applications', admin_user), params: { name: 'application_name', redirect_uri: 'http://', scopes: '' }
+          post api('/applications', admin_user), params: { name: 'application_name', redirect_uri: 'http://', scopes: scopes }
         end.not_to change { Doorkeeper::Application.count }
 
         expect(response).to have_gitlab_http_status(:bad_request)
@@ -36,7 +38,7 @@ RSpec.describe API::Applications, :api do
 
       it 'does not allow creating an application with a forbidden URI format' do
         expect do
-          post api('/applications', admin_user), params: { name: 'application_name', redirect_uri: 'javascript://alert()', scopes: '' }
+          post api('/applications', admin_user), params: { name: 'application_name', redirect_uri: 'javascript://alert()', scopes: scopes }
         end.not_to change { Doorkeeper::Application.count }
 
         expect(response).to have_gitlab_http_status(:bad_request)
@@ -46,7 +48,7 @@ RSpec.describe API::Applications, :api do
 
       it 'does not allow creating an application without a name' do
         expect do
-          post api('/applications', admin_user), params: { redirect_uri: 'http://application.url', scopes: '' }
+          post api('/applications', admin_user), params: { redirect_uri: 'http://application.url', scopes: scopes }
         end.not_to change { Doorkeeper::Application.count }
 
         expect(response).to have_gitlab_http_status(:bad_request)
@@ -56,7 +58,7 @@ RSpec.describe API::Applications, :api do
 
       it 'does not allow creating an application without a redirect_uri' do
         expect do
-          post api('/applications', admin_user), params: { name: 'application_name', scopes: '' }
+          post api('/applications', admin_user), params: { name: 'application_name', scopes: scopes }
         end.not_to change { Doorkeeper::Application.count }
 
         expect(response).to have_gitlab_http_status(:bad_request)
@@ -64,19 +66,59 @@ RSpec.describe API::Applications, :api do
         expect(json_response['error']).to eq('redirect_uri is missing')
       end
 
-      it 'does not allow creating an application without scopes' do
+      it 'does not allow creating an application without specifying `scopes`' do
         expect do
           post api('/applications', admin_user), params: { name: 'application_name', redirect_uri: 'http://application.url' }
         end.not_to change { Doorkeeper::Application.count }
 
         expect(response).to have_gitlab_http_status(:bad_request)
         expect(json_response).to be_a Hash
-        expect(json_response['error']).to eq('scopes is missing')
+        expect(json_response['error']).to eq('scopes is missing, scopes is empty')
+      end
+
+      it 'does not allow creating an application with blank `scopes`' do
+        expect do
+          post api('/applications', admin_user), params: { name: 'application_name', redirect_uri: 'http://application.url', scopes: '' }
+        end.not_to change { Doorkeeper::Application.count }
+
+        expect(response).to have_gitlab_http_status(:bad_request)
+        expect(json_response['error']).to eq('scopes is empty')
+      end
+
+      it 'does not allow creating an application with invalid `scopes`' do
+        expect do
+          post api('/applications', admin_user), params: { name: 'application_name', redirect_uri: 'http://application.url', scopes: 'non_existent_scope' }
+        end.not_to change { Doorkeeper::Application.count }
+
+        expect(response).to have_gitlab_http_status(:bad_request)
+        expect(json_response['message']['scopes'][0]).to eq('doesn\'t match configured on the server.')
+      end
+
+      context 'multiple scopes' do
+        it 'creates an application with multiple `scopes` when each scope specified is seperated by a space' do
+          expect do
+            post api('/applications', admin_user), params: { name: 'application_name', redirect_uri: 'http://application.url', scopes: 'api read_user' }
+          end.to change { Doorkeeper::Application.count }.by 1
+
+          application = Doorkeeper::Application.last
+
+          expect(response).to have_gitlab_http_status(:created)
+          expect(application.scopes.to_s).to eq('api read_user')
+        end
+
+        it 'does not allow creating an application with multiple `scopes` when one of the scopes is invalid' do
+          expect do
+            post api('/applications', admin_user), params: { name: 'application_name', redirect_uri: 'http://application.url', scopes: 'api non_existent_scope' }
+          end.not_to change { Doorkeeper::Application.count }
+
+          expect(response).to have_gitlab_http_status(:bad_request)
+          expect(json_response['message']['scopes'][0]).to eq('doesn\'t match configured on the server.')
+        end
       end
 
       it 'defaults to creating an application with confidential' do
         expect do
-          post api('/applications', admin_user), params: { name: 'application_name', redirect_uri: 'http://application.url', scopes: '', confidential: nil }
+          post api('/applications', admin_user), params: { name: 'application_name', redirect_uri: 'http://application.url', scopes: scopes, confidential: nil }
         end.to change { Doorkeeper::Application.count }.by(1)
 
         expect(response).to have_gitlab_http_status(:created)
@@ -89,7 +131,7 @@ RSpec.describe API::Applications, :api do
     context 'authorized user without authorization' do
       it 'does not create application' do
         expect do
-          post api('/applications', user), params: { name: 'application_name', redirect_uri: 'http://application.url', scopes: '' }
+          post api('/applications', user), params: { name: 'application_name', redirect_uri: 'http://application.url', scopes: scopes }
         end.not_to change { Doorkeeper::Application.count }
 
         expect(response).to have_gitlab_http_status(:forbidden)
diff --git a/spec/requests/api/groups_spec.rb b/spec/requests/api/groups_spec.rb
index 30df47ccc4..8c801e333f 100644
--- a/spec/requests/api/groups_spec.rb
+++ b/spec/requests/api/groups_spec.rb
@@ -758,6 +758,15 @@ RSpec.describe API::Groups do
         expect(json_response['prevent_sharing_groups_outside_hierarchy']).to eq(true)
       end
 
+      it 'does not update visibility_level if it is restricted' do
+        stub_application_setting(restricted_visibility_levels: [Gitlab::VisibilityLevel::INTERNAL])
+
+        put api("/groups/#{group1.id}", user1), params: { visibility: 'internal' }
+
+        expect(response).to have_gitlab_http_status(:bad_request)
+        expect(json_response['message']['visibility_level']).to include('internal has been restricted by your GitLab administrator')
+      end
+
       context 'updating the `default_branch_protection` attribute' do
         subject do
           put api("/groups/#{group1.id}", user1), params: { default_branch_protection: ::Gitlab::Access::PROTECTION_NONE }
@@ -845,6 +854,15 @@ RSpec.describe API::Groups do
         expect(response).to have_gitlab_http_status(:ok)
         expect(json_response['name']).to eq(new_group_name)
       end
+
+      it 'ignores visibility level restrictions' do
+        stub_application_setting(restricted_visibility_levels: [Gitlab::VisibilityLevel::INTERNAL])
+
+        put api("/groups/#{group1.id}", admin), params: { visibility: 'internal' }
+
+        expect(response).to have_gitlab_http_status(:ok)
+        expect(json_response['visibility']).to eq('internal')
+      end
     end
 
     context 'when authenticated as an user that can see the group' do
diff --git a/spec/requests/api/project_attributes.yml b/spec/requests/api/project_attributes.yml
index c5bcedd491..47eccacf47 100644
--- a/spec/requests/api/project_attributes.yml
+++ b/spec/requests/api/project_attributes.yml
@@ -137,6 +137,7 @@ project_setting:
     - has_confluence
     - has_vulnerabilities
     - prevent_merge_without_jira_issue
+    - warn_about_potentially_unwanted_characters
     - previous_default_branch
     - project_id
     - push_rule_id
diff --git a/spec/requests/api/project_import_spec.rb b/spec/requests/api/project_import_spec.rb
index d3b24eb383..0c9e125cc9 100644
--- a/spec/requests/api/project_import_spec.rb
+++ b/spec/requests/api/project_import_spec.rb
@@ -16,6 +16,16 @@ RSpec.describe API::ProjectImport do
     namespace.add_owner(user)
   end
 
+  shared_examples 'requires authentication' do
+    let(:user) { nil }
+
+    it 'returns 401' do
+      subject
+
+      expect(response).to have_gitlab_http_status(:unauthorized)
+    end
+  end
+
   describe 'POST /projects/import' do
     subject { upload_archive(file_upload, workhorse_headers, params) }
 
@@ -32,6 +42,8 @@ RSpec.describe API::ProjectImport do
       allow(ImportExportUploader).to receive(:workhorse_upload_path).and_return('/')
     end
 
+    it_behaves_like 'requires authentication'
+
     it 'executes a limited number of queries' do
       control_count = ActiveRecord::QueryRecorder.new { subject }.count
 
@@ -281,6 +293,10 @@ RSpec.describe API::ProjectImport do
   end
 
   describe 'POST /projects/remote-import' do
+    subject do
+      post api('/projects/remote-import', user), params: params
+    end
+
     let(:params) do
       {
         path: 'test-import',
@@ -288,10 +304,12 @@ RSpec.describe API::ProjectImport do
       }
     end
 
+    it_behaves_like 'requires authentication'
+
     it 'returns NOT FOUND when the feature is disabled' do
       stub_feature_flags(import_project_from_remote_file: false)
 
-      post api('/projects/remote-import', user), params: params
+      subject
 
       expect(response).to have_gitlab_http_status(:not_found)
     end
@@ -315,7 +333,7 @@ RSpec.describe API::ProjectImport do
             .to receive(:execute)
             .and_return(service_response)
 
-          post api('/projects/remote-import', user), params: params
+          subject
 
           expect(response).to have_gitlab_http_status(:created)
           expect(json_response).to include({
@@ -338,7 +356,7 @@ RSpec.describe API::ProjectImport do
             .to receive(:execute)
             .and_return(service_response)
 
-          post api('/projects/remote-import', user), params: params
+          subject
 
           expect(response).to have_gitlab_http_status(:bad_request)
           expect(json_response).to eq({
@@ -350,6 +368,14 @@ RSpec.describe API::ProjectImport do
   end
 
   describe 'GET /projects/:id/import' do
+    it 'public project accessible for an unauthenticated user' do
+      project = create(:project, :public)
+
+      get api("/projects/#{project.id}/import", nil)
+
+      expect(response).to have_gitlab_http_status(:ok)
+    end
+
     it 'returns the import status' do
       project = create(:project, :import_started)
       project.add_maintainer(user)
@@ -376,6 +402,8 @@ RSpec.describe API::ProjectImport do
   describe 'POST /projects/import/authorize' do
     subject { post api('/projects/import/authorize', user), headers: workhorse_headers }
 
+    it_behaves_like 'requires authentication'
+
     it 'authorizes importing project with workhorse header' do
       subject
 
diff --git a/spec/requests/api/projects_spec.rb b/spec/requests/api/projects_spec.rb
index 6e0549d519..49e7c387c8 100644
--- a/spec/requests/api/projects_spec.rb
+++ b/spec/requests/api/projects_spec.rb
@@ -990,7 +990,7 @@ RSpec.describe API::Projects do
 
         expect do
           get api('/projects', admin)
-        end.not_to exceed_query_limit(control.count)
+        end.not_to exceed_query_limit(control)
       end
     end
   end
@@ -3203,6 +3203,15 @@ RSpec.describe API::Projects do
         expect(json_response['visibility']).to eq('private')
       end
 
+      it 'does not update visibility_level if it is restricted' do
+        stub_application_setting(restricted_visibility_levels: [Gitlab::VisibilityLevel::INTERNAL])
+
+        put api("/projects/#{project3.id}", user), params: { visibility: 'internal' }
+
+        expect(response).to have_gitlab_http_status(:bad_request)
+        expect(json_response['message']['visibility_level']).to include('internal has been restricted by your GitLab administrator')
+      end
+
       it 'does not update name to existing name' do
         project_param = { name: project3.name }
 
@@ -3526,6 +3535,19 @@ RSpec.describe API::Projects do
       end
     end
 
+    context 'when authenticated as the admin' do
+      let_it_be(:admin) { create(:admin) }
+
+      it 'ignores visibility level restrictions' do
+        stub_application_setting(restricted_visibility_levels: [Gitlab::VisibilityLevel::INTERNAL])
+
+        put api("/projects/#{project3.id}", admin), params: { visibility: 'internal' }
+
+        expect(response).to have_gitlab_http_status(:ok)
+        expect(json_response['visibility']).to eq('internal')
+      end
+    end
+
     context 'when updating repository storage' do
       let(:unknown_storage) { 'new-storage' }
       let(:new_project) { create(:project, :repository, namespace: user.namespace) }
diff --git a/spec/services/groups/transfer_service_spec.rb b/spec/services/groups/transfer_service_spec.rb
index 889b555174..83337aad6f 100644
--- a/spec/services/groups/transfer_service_spec.rb
+++ b/spec/services/groups/transfer_service_spec.rb
@@ -2,7 +2,7 @@
 
 require 'spec_helper'
 
-RSpec.describe Groups::TransferService do
+RSpec.describe Groups::TransferService, :sidekiq_inline do
   let_it_be(:user) { create(:user) }
   let_it_be(:new_parent_group) { create(:group, :public) }
 
@@ -594,6 +594,59 @@ RSpec.describe Groups::TransferService do
               transfer_service.execute(new_parent_group)
             end
           end
+
+          context 'transferring groups with shared_projects' do
+            let_it_be_with_reload(:shared_project) { create(:project, :public) }
+
+            shared_examples_for 'drops the authorizations of ancestor members from the old hierarchy' do
+              it 'drops the authorizations of ancestor members from the old hierarchy' do
+                expect { transfer_service.execute(new_parent_group) }.to change {
+                  ProjectAuthorization.where(project: shared_project, user: old_group_member).size
+                }.from(1).to(0)
+              end
+            end
+
+            context 'when the group that has existing project share is transferred' do
+              before do
+                create(:project_group_link, :maintainer, project: shared_project, group: group)
+              end
+
+              it_behaves_like 'drops the authorizations of ancestor members from the old hierarchy'
+            end
+
+            context 'when the group whose subgroup has an existing project share is transferred' do
+              let_it_be_with_reload(:subgroup) { create(:group, :private, parent: group) }
+
+              before do
+                create(:project_group_link, :maintainer, project: shared_project, group: subgroup)
+              end
+
+              it_behaves_like 'drops the authorizations of ancestor members from the old hierarchy'
+            end
+          end
+
+          context 'when a group that has existing group share is transferred' do
+            let(:shared_with_group) { group }
+
+            let_it_be(:member_of_shared_with_group) { create(:user) }
+            let_it_be(:shared_group) { create(:group, :private) }
+            let_it_be(:project_in_shared_group) { create(:project, namespace: shared_group) }
+
+            before do
+              shared_with_group.add_developer(member_of_shared_with_group)
+              create(:group_group_link, :maintainer, shared_group: shared_group, shared_with_group: shared_with_group)
+              shared_with_group.refresh_members_authorized_projects
+            end
+
+            it 'retains the authorizations of direct members' do
+              expect { transfer_service.execute(new_parent_group) }.not_to change {
+                ProjectAuthorization.where(
+                  project: project_in_shared_group,
+                  user: member_of_shared_with_group,
+                  access_level: Gitlab::Access::DEVELOPER).size
+              }.from(1)
+            end
+          end
         end
       end
 
diff --git a/spec/services/issues/update_service_spec.rb b/spec/services/issues/update_service_spec.rb
index 29ac7df88e..27e4351241 100644
--- a/spec/services/issues/update_service_spec.rb
+++ b/spec/services/issues/update_service_spec.rb
@@ -6,6 +6,7 @@ RSpec.describe Issues::UpdateService, :mailer do
   let_it_be(:user) { create(:user) }
   let_it_be(:user2) { create(:user) }
   let_it_be(:user3) { create(:user) }
+  let_it_be(:guest) { create(:user) }
   let_it_be(:group) { create(:group, :public) }
   let_it_be(:project, reload: true) { create(:project, :repository, group: group) }
   let_it_be(:label) { create(:label, project: project) }
@@ -24,6 +25,7 @@ RSpec.describe Issues::UpdateService, :mailer do
     project.add_maintainer(user)
     project.add_developer(user2)
     project.add_developer(user3)
+    project.add_guest(guest)
   end
 
   describe 'execute' do
@@ -95,9 +97,7 @@ RSpec.describe Issues::UpdateService, :mailer do
         end
 
         context 'user is a guest' do
-          before do
-            project.add_guest(user)
-          end
+          let(:user) { guest }
 
           it 'does not assign the sentry error' do
             update_issue(opts)
@@ -245,11 +245,7 @@ RSpec.describe Issues::UpdateService, :mailer do
 
         context 'from issue to restricted issue types' do
           context 'without sufficient permissions' do
-            let(:user) { create(:user) }
-
-            before do
-              project.add_guest(user)
-            end
+            let(:user) { guest }
 
             it 'does nothing to the labels' do
               expect { update_issue(issue_type: 'issue') }.not_to change(issue.labels, :count)
@@ -394,12 +390,6 @@ RSpec.describe Issues::UpdateService, :mailer do
       end
 
       context 'when current user cannot admin issues in the project' do
-        let(:guest) { create(:user) }
-
-        before do
-          project.add_guest(guest)
-        end
-
         it 'filters out params that cannot be set without the :admin_issue permission' do
           described_class.new(
             project: project, current_user: guest, params: opts.merge(
@@ -1100,6 +1090,24 @@ RSpec.describe Issues::UpdateService, :mailer do
 
             it_behaves_like 'does not change the severity'
           end
+
+          context 'as guest' do
+            let(:user) { guest }
+
+            it_behaves_like 'does not change the severity'
+
+            context 'and also author' do
+              let(:issue) { create(:incident, project: project, author: user) }
+
+              it_behaves_like 'does not change the severity'
+            end
+
+            context 'and also assignee' do
+              let(:issue) { create(:incident, project: project, assignee_ids: [user.id]) }
+
+              it_behaves_like 'does not change the severity'
+            end
+          end
         end
 
         context 'when severity has been set before' do
diff --git a/workhorse/internal/artifacts/artifacts_upload_test.go b/workhorse/internal/artifacts/artifacts_upload_test.go
index ce078c7855..488636043b 100644
--- a/workhorse/internal/artifacts/artifacts_upload_test.go
+++ b/workhorse/internal/artifacts/artifacts_upload_test.go
@@ -270,7 +270,7 @@ func TestUploadHandlerForMultipleFiles(t *testing.T) {
 	require.NoError(t, s.writer.Close())
 
 	response := testUploadArtifacts(t, s.writer.FormDataContentType(), s.url, s.buffer)
-	require.Equal(t, http.StatusInternalServerError, response.Code)
+	require.Equal(t, http.StatusBadRequest, response.Code)
 }
 
 func TestUploadFormProcessing(t *testing.T) {
diff --git a/workhorse/internal/upload/exif/testdata/takes_lot_of_memory_to_decode.tiff b/workhorse/internal/upload/exif/testdata/takes_lot_of_memory_to_decode.tiff
new file mode 100644
index 0000000000..6935cb130d
Binary files /dev/null and b/workhorse/internal/upload/exif/testdata/takes_lot_of_memory_to_decode.tiff differ
diff --git a/workhorse/internal/upload/rewrite.go b/workhorse/internal/upload/rewrite.go
index 7945fa1f34..3dfab12018 100644
--- a/workhorse/internal/upload/rewrite.go
+++ b/workhorse/internal/upload/rewrite.go
@@ -25,7 +25,10 @@ import (
 )
 
 // ErrInjectedClientParam means that the client sent a parameter that overrides one of our own fields
-var ErrInjectedClientParam = errors.New("injected client parameter")
+var (
+	ErrInjectedClientParam   = errors.New("injected client parameter")
+	ErrMultipleFilesUploaded = errors.New("upload request contains more than one file")
+)
 
 var (
 	multipartUploadRequests = promauto.NewCounterVec(
@@ -114,6 +117,10 @@ func rewriteFormFilesFromMultipart(r *http.Request, writer *multipart.Writer, pr
 }
 
 func (rew *rewriter) handleFilePart(ctx context.Context, name string, p *multipart.Part, opts *filestore.SaveFileOpts) error {
+	if rew.filter.Count() > 0 {
+		return ErrMultipleFilesUploaded
+	}
+
 	multipartFiles.WithLabelValues(rew.filter.Name()).Inc()
 
 	filename := filepath.Base(p.FileName())
@@ -226,7 +233,7 @@ func handleExifUpload(ctx context.Context, r io.Reader, filename string, imageTy
 }
 
 func isTIFF(r io.Reader) bool {
-	_, err := tiff.Decode(r)
+	_, err := tiff.DecodeConfig(r)
 	if err == nil {
 		return true
 	}
diff --git a/workhorse/internal/upload/rewrite_test.go b/workhorse/internal/upload/rewrite_test.go
index 6fc41c3fef..e3f33a0248 100644
--- a/workhorse/internal/upload/rewrite_test.go
+++ b/workhorse/internal/upload/rewrite_test.go
@@ -2,6 +2,7 @@ package upload
 
 import (
 	"os"
+	"runtime"
 	"testing"
 
 	"github.com/stretchr/testify/require"
@@ -29,6 +30,10 @@ func TestImageTypeRecongition(t *testing.T) {
 			filename: "exif/testdata/sample_exif_invalid.jpg",
 			isJPEG:   false,
 			isTIFF:   false,
+		}, {
+			filename: "exif/testdata/takes_lot_of_memory_to_decode.tiff", // File from https://gitlab.com/gitlab-org/gitlab/-/issues/341363
+			isJPEG:   false,
+			isTIFF:   true,
 		},
 	}
 
@@ -36,8 +41,16 @@ func TestImageTypeRecongition(t *testing.T) {
 		t.Run(test.filename, func(t *testing.T) {
 			input, err := os.Open(test.filename)
 			require.NoError(t, err)
+
+			var m runtime.MemStats
+			runtime.ReadMemStats(&m)
+			start := m.TotalAlloc
+
 			require.Equal(t, test.isJPEG, isJPEG(input))
 			require.Equal(t, test.isTIFF, isTIFF(input))
+
+			runtime.ReadMemStats(&m)
+			require.Less(t, m.TotalAlloc-start, uint64(50000), "must take reasonable amount of memory to recognise the type")
 		})
 	}
 }
diff --git a/workhorse/internal/upload/uploads.go b/workhorse/internal/upload/uploads.go
index 7a93fa4a9d..8f4c8bb95f 100644
--- a/workhorse/internal/upload/uploads.go
+++ b/workhorse/internal/upload/uploads.go
@@ -21,6 +21,7 @@ type MultipartFormProcessor interface {
 	ProcessField(ctx context.Context, formName string, writer *multipart.Writer) error
 	Finalize(ctx context.Context) error
 	Name() string
+	Count() int
 }
 
 func HandleFileUploads(w http.ResponseWriter, r *http.Request, h http.Handler, preauth *api.Response, filter MultipartFormProcessor, opts *filestore.SaveFileOpts) {
@@ -34,6 +35,8 @@ func HandleFileUploads(w http.ResponseWriter, r *http.Request, h http.Handler, p
 		switch err {
 		case ErrInjectedClientParam:
 			helper.CaptureAndFail(w, r, err, "Bad Request", http.StatusBadRequest)
+		case ErrMultipleFilesUploaded:
+			helper.CaptureAndFail(w, r, err, "Uploading multiple files is not allowed", http.StatusBadRequest)
 		case http.ErrNotMultipart:
 			h.ServeHTTP(w, r)
 		case filestore.ErrEntityTooLarge:
diff --git a/workhorse/internal/upload/uploads_test.go b/workhorse/internal/upload/uploads_test.go
index 5fae5cf7bc..a655cabd2e 100644
--- a/workhorse/internal/upload/uploads_test.go
+++ b/workhorse/internal/upload/uploads_test.go
@@ -18,7 +18,6 @@ import (
 	"github.com/stretchr/testify/require"
 
 	"gitlab.com/gitlab-org/gitlab/workhorse/internal/api"
-	"gitlab.com/gitlab-org/gitlab/workhorse/internal/filestore"
 	"gitlab.com/gitlab-org/gitlab/workhorse/internal/helper"
 	"gitlab.com/gitlab-org/gitlab/workhorse/internal/objectstore/test"
 	"gitlab.com/gitlab-org/gitlab/workhorse/internal/proxy"
@@ -28,11 +27,7 @@ import (
 
 var nilHandler = http.HandlerFunc(func(http.ResponseWriter, *http.Request) {})
 
-type testFormProcessor struct{}
-
-func (a *testFormProcessor) ProcessFile(ctx context.Context, formName string, file *filestore.FileHandler, writer *multipart.Writer) error {
-	return nil
-}
+type testFormProcessor struct{ SavedFileTracker }
 
 func (a *testFormProcessor) ProcessField(ctx context.Context, formName string, writer *multipart.Writer) error {
 	if formName != "token" && !strings.HasPrefix(formName, "file.") && !strings.HasPrefix(formName, "other.") {
@@ -45,10 +40,6 @@ func (a *testFormProcessor) Finalize(ctx context.Context) error {
 	return nil
 }
 
-func (a *testFormProcessor) Name() string {
-	return ""
-}
-
 func TestUploadTempPathRequirement(t *testing.T) {
 	apiResponse := &api.Response{}
 	preparer := &DefaultPreparer{}
@@ -259,6 +250,38 @@ func TestUploadProcessingField(t *testing.T) {
 	require.Equal(t, 500, response.Code)
 }
 
+func TestUploadingMultipleFiles(t *testing.T) {
+	testhelper.ConfigureSecret()
+
+	tempPath, err := ioutil.TempDir("", "uploads")
+	require.NoError(t, err)
+	defer os.RemoveAll(tempPath)
+
+	var buffer bytes.Buffer
+
+	writer := multipart.NewWriter(&buffer)
+	_, err = writer.CreateFormFile("file", "my.file")
+	require.NoError(t, err)
+	_, err = writer.CreateFormFile("file", "my.file")
+	require.NoError(t, err)
+	require.NoError(t, writer.Close())
+
+	httpRequest, err := http.NewRequest("PUT", "/url/path", &buffer)
+	require.NoError(t, err)
+	httpRequest.Header.Set("Content-Type", writer.FormDataContentType())
+
+	response := httptest.NewRecorder()
+	apiResponse := &api.Response{TempPath: tempPath}
+	preparer := &DefaultPreparer{}
+	opts, _, err := preparer.Prepare(apiResponse)
+	require.NoError(t, err)
+
+	HandleFileUploads(response, httpRequest, nilHandler, apiResponse, &testFormProcessor{}, opts)
+
+	require.Equal(t, 400, response.Code)
+	require.Equal(t, "Uploading multiple files is not allowed\n", response.Body.String())
+}
+
 func TestUploadProcessingFile(t *testing.T) {
 	tempPath, err := ioutil.TempDir("", "uploads")
 	require.NoError(t, err)