CVE-2026-8857: Mediawiki

High severity, CVSS 8.8. EPSS: 2.1% chance of exploitation in the next 30 days.

A vulnerability in Wikimedia Foundation timeline. This vulnerability is associated with program files scripts/EasyTimeline.Pl, includes/Timeline.Php. This issue affects timeline: from * before 1.46.0, 1.45.4, 1.44.6, 1.43.9.

Affected products

• Mediawiki Mediawiki: from 1.43.0, before 1.43.9 (fixed in 1.43.9); from 1.44.0, before 1.44.6 (fixed in 1.44.6); from 1.45.0, before 1.45.4 (fixed in 1.45.4)

Published 2026-07-01. Last modified 2026-07-09.