Impact
It's possible using comments to inject CSS that would transform the full wiki in a link area leading to a malicious page. All versions of XWiki are impacted by this kind of attack.
Patches
The problem has been patched not by preventing injecting CSS in comments, which is currently a feature of XWiki, but by requiring confirmation from users when driving them to untrusted domains after clicking on a link, thus preventing any click-jacking attack.
This security measure has been put in place in XWiki 17.9.0, 17.4.6, 16.10.13.
Workarounds
There's no out-of-the-box workaround, but it should be possible to partly reuse the javascript code provided for the security measure in a JSX object inside the wiki, to request the same kind of confirmation.
References
For more information
If you have any questions or comments about this advisory:
Attribution
Thanks Tomas Keech (Sentrium Security Ltd) for reporting this vulnerability.
Impact
It's possible using comments to inject CSS that would transform the full wiki in a link area leading to a malicious page. All versions of XWiki are impacted by this kind of attack.
Patches
The problem has been patched not by preventing injecting CSS in comments, which is currently a feature of XWiki, but by requiring confirmation from users when driving them to untrusted domains after clicking on a link, thus preventing any click-jacking attack.
This security measure has been put in place in XWiki 17.9.0, 17.4.6, 16.10.13.
Workarounds
There's no out-of-the-box workaround, but it should be possible to partly reuse the javascript code provided for the security measure in a JSX object inside the wiki, to request the same kind of confirmation.
References
For more information
If you have any questions or comments about this advisory:
Attribution
Thanks Tomas Keech (Sentrium Security Ltd) for reporting this vulnerability.