CVE-2020-25812
An issue was discovered in MediaWiki 1.34.x before 1.34.4. On Special:Contributions, the NS filter uses unescaped messages as keys in the option key for an HTMLForm specifier. This is vulnerable to a mild XSS if one of those messages is changed to include raw HTML.
Date published : 2020-09-27
https://lists.wikimedia.org/pipermail/mediawiki-l/2020-September/048480.html