CVE-2023-22912: Mediawiki

Medium severity, CVSS 5.3. EPSS: 0.4% chance of exploitation in the next 30 days.

An issue was discovered in MediaWiki before 1.35.9, 1.36.x through 1.38.x before 1.38.5, and 1.39.x before 1.39.1. CheckUser TokenManager insecurely uses AES-CTR encryption with a repeated (aka re-used) nonce, allowing an adversary to decrypt.

Affected products

• Mediawiki Mediawiki: before 1.35.9 (fixed in 1.35.9); from 1.36.0, before 1.38.5 (fixed in 1.38.5); version 1.39.0 only

Published 2023-01-20. Last modified 2026-06-17.