CVE-2023-37255: Mediawiki

Medium severity, CVSS 6.1. EPSS: 0.5% chance of exploitation in the next 30 days.

An issue was discovered in the CheckUser extension for MediaWiki through 1.39.3. In Special:CheckUser, a check of the "get edits" type is vulnerable to HTML injection through the User-Agent HTTP request header.

Affected products

• Mediawiki Mediawiki: up to and including 1.39.3

Published 2023-06-29. Last modified 2026-06-17.