Description
Incomplete blacklist vulnerability in Sanitizer::checkCss in MediaWiki before 1.19.9, 1.20.x before 1.20.8, and 1.21.x before 1.21.3 allows remote attackers to conduct cross-site scripting (XSS) attacks via a \b (backspace) character in CSS.
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | mediawiki | 1:1.19.8+dfsg-2.2 | — |
| Debian 13 | mediawiki | 1:1.19.8+dfsg-2.2 | — |
| Debian 12 | mediawiki | 1:1.19.8+dfsg-2.2 | — |
| Debian 7 | mediawiki | 1:1.19.14+dfsg-0+deb7u1 | DSA-2891-1 |
| Debian 7 | mediawiki-extensions | 3.5~deb7u1 | DSA-2891-1 |
Advisories 1
- DSA-2891-1 mediawiki - security update Debian Security (DSA / DLA) · Mar 9, 2026
References
- 63760 vdb-entry
- 57472 third-party-advisory
- DSA-2891 vendor-advisory
- [MediaWiki-announce] 20131114 MediaWiki Security Release: 1.21.3, 1.20.8 and 1.19.9 mailing-list
- FEDORA-2013-21856 vendor-advisory
- FEDORA-2013-21874 vendor-advisory
- https://bugzilla.wikimedia.org/show_bug.cgi?id=55332