CVE-2026-79988: Craft CMS CMS

High severity, CVSS 8.7. EPSS: 0.5% chance of exploitation in the next 30 days.

The Twig sandbox mechanism in Craft CMS is configured to allow dangerous functionality from the Yii framework, leading to authenticated RCE similar to previously disclosed vulnerabilities.

Affected products

• Craft CMS CMS: from 4.0.0-RC1, before 4.18.3 (fixed in 4.18.3); from 5.0.0-RC1, before 5.10.7 (fixed in 5.10.7)

Published 2026-08-27. Last modified 2026-08-28.