CVE-2026-41128: Craft CMS CMS

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

Craft CMS is a content management system (CMS). In versions 5.6.0 through 5.9.14, the `actionSavePermissions()` endpoint allows a user with only `viewUsers` permission to remove arbitrary users from all user groups. While `_saveUserGroups()` enforces per-group authorization for additions, it performs no equivalent authorization check for removals, so submitting an empty `groups` value removes all existing group memberships. Version 5.9.15 contains a patch.

Affected products

• Craft CMS CMS: from 5.6.0, before 5.9.15 (fixed in 5.9.15)

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