What’s Vulnerable › Vulnerabilities

CVE-2026-109308: Craft CMS 4.0.0 before 4.18.7 and 5.0.0 before 5.10.14 RCE via actionCacheUpdates Behavior Injection

• Severity: high (CVSS 8.8 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.5% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-10-12 · updated 2026-10-16
• Weakness: CWE-94

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.

Affected products

• craftcms cms: from 4.0.0 before 4.18.7; from 5.0.0 before 5.10.14 — fixed in 4.18.7, 5.10.14

How to fix

Upgrade to a fixed version: craftcms cms 4.18.7, 5.10.14. Check the vendor advisory for mitigations.

References

• https://github.com/craftcms/cms/security/advisories/GHSA-5m2g-hhqr-84pc
• https://www.vulncheck.com/advisories/craft-cms-4.0.0-before-4.18.7-and-5.0.0-before-5.10.14-rce-via-actioncacheupdates-behavior-injection

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