Vulnerability · Published Apr 21, 2026 · Assigned by GitHub_M

CVE-2026-41128Craft CMS has a Missing Authorization Check on User Group Removal via save-permissions Action

Medium 5.3

In plain English

A medium-severity missing authorization in cms from craftcms. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 16% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 4.0)5.3Medium

Exploit odds (30 days)0.2%top 83.8% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

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 packages & fixed versions

Ecosystem	Package	Fixed in	Advisory
Packagist	craftcms/cms	5.9.15	GHSA-jq2f-59pj-p3m3

Affected products (as reported)

Vendor	Product	Versions
craftcms	cms	>= 5.6.0, < 5.9.15

Weakness: CWE-862 · Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N

References

https://github.com/craftcms/cms/security/advisories/GHSA-jq2f-59pj-p3m3 x_refsource_CONFIRM
https://github.com/craftcms/cms/commit/b135384808ad43fcf8836a9dd9b877fb0087bc27 x_refsource_MISC