Review reviewHigh

CVE-2026-56382

craftcms cms

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...

CVSS: 8.6
EPSS: 0.49%
CISA KEV: Not listed
Published: 2026.06.21

PRIORITY ASSESSMENT

Review review

The CVSS severity warrants an early asset and exposure review.

Known exploitationNot established by KEV

Exploit probability0.49%

Technical severityCVSS 8.6

Vulnerability overview

Affected product and versions

Product: craftcms cms
Affected versions: 5.5.0
Fixed versions: No verified fixed-version field is available yet

Recommended response sequence

Confirm exposure before applying a vendor-supported change.

Full remediation guide

1
Identify
Confirm that craftcms cms and an affected version are present.
2
Prioritize
Combine exploitation signals with asset exposure and business criticality.
3
Remediate
Follow the vendor advisory or supported update path and preserve rollback options.
4
Verify
Recheck the version, service health, access paths, and relevant logs.

Technical data

CVSS vector: 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
CWE: CWE-94