diff --git a/src/matrix/net/request/xhr.js b/src/matrix/net/request/xhr.js
index 6685131e..ad4a33fc 100644
--- a/src/matrix/net/request/xhr.js
+++ b/src/matrix/net/request/xhr.js
@@ -68,7 +68,7 @@ export function xhrRequest(url, options) {
         const {status} = xhr;
         let body = null;
         if (xhr.getResponseHeader("Content-Type") === "application/json") {
-            body = JSON.parse(body);
+            body = JSON.parse(xhr.responseText);
         }
         return {status, body};
     });