CVE-2026-56382: Craft CMS - Remote Code Execution via Missing Config Sanitization in FieldsController

Severity: high (CVSS 7.2 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.7% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-06-21 · updated 2026-10-25
Weakness: CWE-94

Description

Craft CMS (composer package craftcms/cms) versions >= 5.5.0 and <= 5.9.13 contain a remote code execution vulnerability in the FieldsController::actionRenderCardPreview() method, which passes the fieldLayoutConfig POST parameter directly to Fields::createLayout() without calling Component::cleanseConfig(). An authenticated admin user can inject Yii2 event handlers (e.g., 'on init' keys) via the fieldLayoutConfig parameter to execute arbitrary PHP code and disclose sensitive information (such as environment variables containing database credentials and CRAFT_SECURITY_KEY). The issue is fixed in version 5.9.14.

Affected products

craftcms cms: from 5.5.0 before 5.9.14 — fixed in 5.9.14

How to fix

Upgrade to a fixed version: craftcms cms 5.9.14. Check the vendor advisory for mitigations.

References

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