CVE-2021-31547: Mediawiki

Medium severity, CVSS 4.3. EPSS: 0.9% chance of exploitation in the next 30 days.

An issue was discovered in the AbuseFilter extension for MediaWiki through 1.35.2. Its AbuseFilterCheckMatch API reveals suppressed edits and usernames to unprivileged users through the iteration of crafted AbuseFilter rules.

Affected products

• Mediawiki Mediawiki: up to and including 1.35.2

Published 2021-04-22. Last modified 2026-06-17.