CVE-2026-33157
Craft CMS: Potential authenticated Remote Code Execution via malicious attached Behavior
Craft CMS is a content management system (CMS). From version 5.6.0 to before version 5.9.13, a Remote Code Execution (RCE) vulnerability exists in Craft CMS, it can be exploited by any authenticated user with control panel access. This is a bypass of a previous fix. The existing patches add cleanseConfig() to assembleLayoutFromPost() and various FieldsController actions to strip Yii2 behavior/event injection keys ("as" and "on" prefixed keys). However, the fieldLayouts parameter in ElementIndexesController::actionFilterHud() is passed directly to FieldLayout::createFromConfig() without any sanitization, enabling the same behavior injection attack chain. This issue has been patched in version 5.9.13.
- Affected
- craftcms · cms
- CVSS v4.0 GITHUB
- 8.6 HIGH
CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - CVSS v4.0 GitHub
- 8.7 HIGH
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N - CVSS v3.1 NVD
- 7.2 HIGH
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H - EPSS
- 1.06% chance of exploitation in the next 30 days, 64th percentile
- Published
- 2026-03-24
- Updated
- 2026-03-25
Proof-of-concept exploits (1)
- TRX-0/CVE-2026-33157-craftcms-rce0★ · 2026-09-21
Security advisories
- craftcms/cms/security/advisories/GHSA-2fph-6v5w-89hh
- advisories/GHSA-2fph-6v5w-89hh
- craftcms/cms/commit/97e90b4bdee369c1af3ca77a77531132df240e4e