Greetings-

With the security/maintenance release of MediaWiki 1.39.16/1.43.6/1.44.3/1.45.1, we would also like to provide this supplementary announcement of MediaWiki extensions and skins with now-public Phabricator tasks, security patches and backports [1]:

Citizen + (GHSA-g955-vw6w-v6pp, CVE-2025-62508) - Stored XSS in sticky header button messages https://github.com/StarCitizenTools/mediawiki-skins-Citizen/security/advisor...

VisualData + (T387008, CVE-2026-0668) - VisualData extension: Regular Expression Denial of Service (ReDoS) via crafted user input https://gerrit.wikimedia.org/r/q/Ie08d9a8ceb2c9a22a635cfc27964353f14072dbf https://gerrit.wikimedia.org/r/q/Ifbf9c2ade621226e14fe852f3217293772bf8bb8 https://gerrit.wikimedia.org/r/q/I893a9fca694a2613e29e149dea2d76d7f06063e5 https://gerrit.wikimedia.org/r/q/I4ff2737c9f0ba805267d1fc8296e7cff61241ee3

CSS + (T401526, CVE-2026-0669) - Path Traversal vulnerability in CSS extension on certain web servers https://gerrit.wikimedia.org/r/q/Ia15bf3f2e5a341868568492a736ac3dbf706c22e

UploadWizard + (T407157, CVE-2026-0671) - Multiple stored i18n/message-key XSSes in UploadWizard https://gerrit.wikimedia.org/r/q/I16de2211594ea9a686868ad7789f9879bf981fa1

ProofreadPage + (T409423, CVE-2026-0670) - Stored XSS through a system message and a user-provided parameter in ProofreadPage https://gerrit.wikimedia.org/r/q/I7c028db5ed81843aacd596b0ee4dc2980f5b6e3c

Wikibase + (T409737, CVE-2026-22710) - Stored XSS through autocomment system messages https://gerrit.wikimedia.org/r/q/I8505700afda8096ef4e183280494232152767004

Monaco + (T411126, CVE-2026-22714) - i18n XSS, DoS and config SQLI https://gerrit.wikimedia.org/r/q/I00b2e369fa189803380ca7409022a11b670d2500

GrowthExperiments + (T411144, CVE-2026-22713) - Stored XSS through edit summaries https://gerrit.wikimedia.org/r/q/Iff01940a163ed87ec52f3a64ba6b2dbfa2759df3

ApprovedRevs + (T412068, CVE-2026-22712) - Bypassing the inline CSS sanitizer https://gerrit.wikimedia.org/r/q/Iee1bf1cbc8a519899e7f9dde508856bd4e5a5d2a

CampaignEvents + (T410560, CVE-2026-0817) - CampaignEvents API missing authorization exposes meeting and chat URLs https://gerrit.wikimedia.org/r/q/I7ed0049691258c8bd2555e599b9b88490fbe3358

The Wikimedia Security Team recommends updating these extensions and/or skins to the current master branch or relevant, supported release branch [2] as soon as possible. Some of the referenced Phabricator tasks above _may_ still be private. Unfortunately, when security issues are reported, sometimes sensitive information is exposed and since Phabricator is historical, we cannot make these tasks public without exposing this sensitive information. If you have any additional questions or concerns regarding this update, please feel free to contact security@wikimedia.org or file a security task within Phabricator [3].

[1] https://phabricator.wikimedia.org/T404620 [2] https://www.mediawiki.org/wiki/Version_lifecycle [3] https://www.mediawiki.org/wiki/Reporting_security_bugs