CVE-2021-31550: Mediawiki

Medium severity, CVSS 5.4. EPSS: 0.5% chance of exploitation in the next 30 days.

An issue was discovered in the CommentBox extension for MediaWiki through 1.35.2. Via crafted configuration variables, a malicious actor could introduce XSS payloads into various layers.

Affected products

• Mediawiki Mediawiki: up to and including 1.35.2

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