Description
An issue was discovered in MediaWiki before 1.35.7, 1.36.x and 1.37.x before 1.37.3, and 1.38.x before 1.38.1. XSS can occur in configurations that allow a JavaScript payload in a username. After account creation, when it sets the page title to "Welcome" followed by the username, the username is not escaped: SpecialCreateAccount::successfulAction() calls ::showSuccessPage() with a message as second parameter, and OutputPage::setPageTitle() uses text().
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 | 1:1.35.7-1 | — |
| Debian 13 | mediawiki | 1:1.35.7-1 | — |
| Debian 12 | mediawiki | 1:1.35.7-1 | — |
| Debian 11 | mediawiki | 1:1.35.8-1~deb11u1 | DSA-5246-1 |
| Debian 10 | mediawiki | 1:1.31.16-1+deb10u3 | DLA-3117-1 |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.10 | mediawiki | No fix yet | — |
| Ubuntu 26.04 LTS | mediawiki | No fix yet | — |
| Ubuntu 25.10 | mediawiki | No fix yet | — |
| Ubuntu 18.04 LTS | mediawiki | No fix yet | — |
Show 3 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 24.04 LTS | mediawiki | No fix yet | — |
| Ubuntu Pro 22.04 LTS | mediawiki | No fix yet | — |
| Ubuntu Pro 20.04 LTS | mediawiki | No fix yet | — |
Advisories 3
- DSA-5246-1 mediawiki - security update Debian Security (DSA / DLA) · Mar 9, 2026
- DLA-3117-1 mediawiki - security update Debian Security (DSA / DLA) · Mar 9, 2026
- WID-SEC-2022-0557 MediaWiki: Mehrere Schwachstellen ermöglichen Cross-Site Scripting BSI CERT-Bund (WID) · May 21, 2023
References
- https://phabricator.wikimedia.org/T308471
- FEDORA-2022-f83aec6d57 vendor-advisory
- FEDORA-2022-bca2c95559 vendor-advisory
- [debian-lts-announce] 20220922 [SECURITY] [DLA 3117-1] mediawiki security update mailing-list
- DSA-5246 vendor-advisory
- GLSA-202305-24 vendor-advisory