Executive brief
A security vulnerability exists in the Wikimedia AbuseFilter, a tool used to detect and prevent malicious edits on MediaWiki sites. An authenticated user could potentially access sensitive information that should be restricted. This could lead to the exposure of internal filter details or other non-public data, potentially helping bad actors bypass site protections.
Technical details
An information disclosure vulnerability (CWE-200) exists in the Wikimedia Foundation AbuseFilter extension. The flaw is located within the 'includes/Api/QueryAbuseFilters.php' component. A remote attacker with low-level authenticated privileges can exploit this vulnerability via the network to access sensitive information. The issue affects multiple versions of AbuseFilter and has been addressed in versions 1.46.0, 1.45.4, 1.44.6, and 1.43.9. Exploitation does not require user interaction or complex attack timing.
Affected products
- Wikimedia Foundation AbuseFilter before 1.46.0, 1.45.4, 1.44.6, 1.43.9
Timeline
- 2026-07-01: advisory: CVE-2026-58027 published by Wikimedia Foundation