CVE-2026-58028 Wikimedia Foundation CVE debrief

Who should care

Users of MediaWiki and CentralAuth versions prior to 1.46.0, 1.45.4, 1.44.6, and 1.43.9 should apply patches to prevent XSS attacks. This includes operators, platform administrators, vulnerability management teams, and security teams who need to review and update affected program files, implement additional security measures, and monitor for potential attacks.

Technical summary

The vulnerability is caused by improper neutralization of input during web page generation in MediaWiki and CentralAuth, potentially leading to XSS attacks. Affected program files include includes/Api/ApiFormatBase.Php, includes/Api/ApiHelp.Php, includes/ResourceLoader/Module.Php, includes/Hooks/Handlers/PageDisplayHookHandler.Php, and includes/LogFormatter/PermissionChangeLogFormatter.Php. Users should review and update these files, and implement additional security measures to prevent attacks.

Defensive priority

High priority for MediaWiki and CentralAuth users due to potential for XSS attacks

Recommended defensive actions

• Apply patches to MediaWiki and CentralAuth versions prior to 1.46.0, 1.45.4, 1.44.6, and 1.43.9
• Review and update affected program files
• Implement additional security measures to prevent XSS attacks
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up
• Review compensating controls for exposed systems while remediation is scheduled and verified
• Check relevant monitoring, detection, and logs for exposed assets that need extra review
• Track exceptions, retest remediated assets, and close the item only after evidence is documented

Evidence notes

Evidence from official CVE and NVD sources indicate a high severity vulnerability in MediaWiki and CentralAuth, with potential for XSS attacks. However, CVSS score and severity are not provided. Defenders should verify affected product deployments, review official advisories, and plan vendor-supported updates or mitigations. Compensating controls and monitoring may be necessary for exposed systems.

Official resources