TYPO3-CORE-SA-2026-016: Broken Access Control in File Abstraction Layer
It has been discovered that TYPO3 CMS is susceptible to broken access control.
- Component Type: TYPO3 CMS
- Subcomponent: Core API (ext:core)
- 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: Low
- Suggested CVSS: CVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N
- References: CVE-2026-49738, CWE-22
Problem Description
The path allowance check in GeneralUtility::isAllowedAbsPath() performed a plain string prefix comparison without requiring a directory separator boundary, causing a path like /var/www/html-other/secret.yaml to be incorrectly accepted as valid when the project root was /var/www/html. Administrator users with access to the File Abstraction Layer were able to create new file storage definitions pointing to directories outside the project root, bypassing this path check.
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 Wolfgang Klinger 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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