CVE-2026-55792

Craft CMS is a content management system (CMS). In versions starting from 4.0.0-RC1 and prior to 4.18.0, and 5.0.0-RC1 and above, prior to 5.10.0, the dataUrl() Twig function is included in Craft’s Twig sandbox allowlist, allowing any control panel user granted the utility:system-messages permission to embed a file-reading payload into system email templates. When those emails are sent, the server reads the target file and returns its contents as a base64-encoded data URL embedded in the email body. The .env file, which typically contains the database password, CRAFT_SECURITY_KEY, and third-party API keys, passes all of Craft’s existing dataUrl() protection checks and is fully exfiltrated. Obtaining CRAFT_SECURITY_KEY enables an attacker to forge session tokens and escalate to full admin account takeover. This issue has been fixed in versions 4.18.0 and 5.10.0.

CVSS

No CVSS.

References

Link	Resource
https://github.com/craftcms/cms/pull/18559
https://github.com/craftcms/cms/security/advisories/GHSA-287w-mxq6-x2cp
https://github.com/craftcms/cms/pull/18559

Configurations

No configuration.

History

No history.

Information

Published : 2026-07-02 00:16

Updated : 2026-07-02 15:17

NVD link : CVE-2026-55792

Mitre link : CVE-2026-55792

CVE.ORG link : CVE-2026-55792

JSON object : View

Products Affected

No product.

CWE

CWE-200

Exposure of Sensitive Information to an Unauthorized Actor

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