There is a potential DOM based cross-site scripting issue in rails-ujs which leverages the Clipboard API to target HTML elements that are assigned the contenteditable attribute. This has the potential to occur when pasting malicious HTML content from the clipboard that includes a data-method, data-remote or data-disable-with attribute.
This vulnerability has been assigned the CVE identifier CVE-2023-23913.
Versions Affected: >= 5.1.0 Not affected: < 5.1.0 Fixed Versions: 6.1.7.3, 7.0.4.3
Impact
If the specified malicious HTML clipboard content is provided to a contenteditable element, this could result in the arbitrary execution of javascript on the origin in question.
Releases
The FIXED releases are available at the normal locations.
Workarounds
We recommend that all users upgrade to one of the FIXED versions. In the
meantime, users can attempt to mitigate this vulnerability by removing the contenteditable attribute from elements in pages that rails-ujs will interact with.
Patches
To aid users who aren’t able to upgrade immediately we have provided patches for the two supported release series. They are in git-am format and consist of a single changeset.
- rails-ujs-data-method-contenteditable-6-1.patch - Patch for 6.1 series
- rails-ujs-data-method-contenteditable-7-0.patch - Patch for 7.0 series
Please note that only the 7.0.Z and 6.1.Z series are supported at present, and 6.0.Z for severe vulnerabilities. Users of earlier unsupported releases are advised to upgrade as soon as possible as we cannot guarantee the continued availability of security fixes for unsupported releases.
Credits
We would like to thank ryotak for reporting this!
rails-ujs-data-method-contenteditable-6-1.patch (8.5 KB) rails-ujs-data-method-contenteditable-7-0.patch (8.5 KB) rails-ujs-data-method-contenteditable-main.patch (8.9 KB)