CVE-2026-109308: Improper Control of Generation of Code ('Code Injection') in craftcms cms
Description
Craft CMS 4.0.0 before 4.18.7 and 5.0.0 before 5.10.14 passes the raw 'updates' request parameter in AppController::actionCacheUpdates to UpdatesModel without Component::cleanseConfig(), allowing behavior and event-handler injection. Authenticated control panel users with the performUpdates permission or Updates-utility access can supply 'as' or 'on' keys, such as an AttributeTypecastBehavior gadget, to execute arbitrary code.
CVSS v4.0
Score 8.7high
Affected software
craftcms
cms
craftcms
cms
pkg:github/craftcms/cmsRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-109308 is a code injection vulnerability in Craft CMS affecting versions 4.0.0 up to but not including 4.18.7 and 5.0.0 up to but not including 5.10.14. The flaw arises from the AppController::actionCacheUpdates method passing the raw 'updates' request parameter to UpdatesModel without sanitization by Component::cleanseConfig(). Authenticated users with the performUpdates permission or Updates-utility access can supply specially crafted 'as' or 'on' keys, such as an AttributeTypecastBehavior gadget, to inject and execute arbitrary code within the application context.
Potential Impact
Successful exploitation allows authenticated users with specific update permissions to execute arbitrary code on the server, potentially leading to full compromise of the affected system. The vulnerability requires authentication and specific permissions, limiting exposure to authorized users only. There are no known exploits in the wild at this time.
Mitigation Recommendations
A fix is available in Craft CMS versions 4.18.7 and later, and 5.10.14 and later. Users should upgrade to these versions to remediate the vulnerability. No additional mitigations are specified.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- VulnCheck
- Date Reserved
- 2026-10-12T14:14:27.021Z
- Cvss Version
- 4.0
- State
- PUBLISHED
Threat ID: 6acd0c132cdf04f656b11bea
Added to database: 10/12/2026, 16:34:27 UTC
Last enriched: 10/12/2026, 17:18:59 UTC
Last updated: 10/12/2026, 21:46:49 UTC
Views: 9
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