TYPO3-CORE-SA-2026-015: Broken Access Control in Backend API

• Component Type: TYPO3 CMS
• Subcomponent: Backend API (ext:backend)
• Release Date: June 9, 2026
• Vulnerability Type: Broken Access Control
• Affected Versions: 10.0.0-10.4.56, 11.0.0-11.5.50, 12.0.0-12.4.45, 13.0.0-13.4.30, 14.0.0-14.3.2
• Severity: Medium
• Suggested CVSS: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N
• References: CVE-2026-47352, CWE-862

Problem Description

Authenticated backend users were able to retrieve file metadata via several Backend API routes without proper permission checks, allowing access to files outside their permitted file mounts or storages.

Solution

Update to TYPO3 versions 10.4.57 ELTS, 11.5.51 ELTS, 12.4.46 ELTS, 13.4.31 LTS, 14.3.3 LTS that fix the problem described.

Credits

Thanks to Phong Lan for reporting this issue, and to TYPO3 core & security team member Oliver Hader for fixing it.

General Advice

Follow the recommendations that are given in the TYPO3 Security Guide. Please subscribe to the typo3-announce mailing list.

General Note

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