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CVE-2026-49738 TYPO3 CVE debrief

A vulnerability in TYPO3 CMS, tracked as CVE-2026-49738, allows administrator users with access to the File Abstraction Layer to create new file storage definitions pointing to directories outside the project root. This is possible due to a flawed path allowance check in GeneralUtility::isAllowedAbsPath(), which performs a plain string prefix comparison without requiring a directory separator boundary. This issue affects TYPO3 CMS versions before 10.4.57, 11.0.0-11.5.51, 12.0.0-12.4.46, 13.0.0-13.4.31, and 14.0.0-14.3.3.

Vendor
TYPO3
Product
TYPO3 CMS
CVSS
LOW 2.1
CISA KEV
Not listed in stored evidence
Original CVE published
2026-06-09
Original CVE updated
2026-07-15
Advisory published
2026-06-09
Advisory updated
2026-07-15

Who should care

Administrators and users of TYPO3 CMS, especially those with administrator privileges and access to the File Abstraction Layer, should be aware of this vulnerability and take necessary actions to mitigate it.

Technical summary

The path allowance check in GeneralUtility::isAllowedAbsPath() is vulnerable to a path traversal attack. The check performs a plain string prefix comparison without requiring a directory separator boundary. This allows an attacker to create file storage definitions pointing to directories outside the project root.

Defensive priority

Low

Recommended defensive actions

  • Upgrade to a patched version of TYPO3 CMS (10.4.57, 11.5.51, 12.4.46, 13.4.31, or 14.3.3, or later).
  • Restrict access to the File Abstraction Layer to prevent administrator users from creating new file storage definitions.

Evidence notes

The CVE-2026-49738 vulnerability has a CVSS score of 2.1 and is classified as LOW severity. The vulnerability was published on June 9, 2026, and last modified on the same day.

Sources and references

Verified primary and authoritative sources

  • CVE-2026-49738 CVE Program record

    Publisher, destination, and source semantics verified

    URL: https://www.cve.org/CVERecord?id=CVE-2026-49738

    CVE Program - Official CVE Program record with source-provided CVE metadata.

  • CVE-2026-49738 NVD vulnerability detail

    Publisher, destination, and source semantics verified

    URL: https://nvd.nist.gov/vuln/detail/CVE-2026-49738

    NIST National Vulnerability Database - Official NIST NVD detail page and source-specific vulnerability assessment.

Supplemental references

  • Source reference

    Unverified legacy reference

    URL: https://github.com/TYPO3/typo3/commit/150a983a5d687cedcfc33bbe9c335d9a13fd05e5

    f4fb688c-4412-4426-b4b8-421ecf27b14a

  • Source reference

    Unverified legacy reference

    URL: https://github.com/TYPO3/typo3/commit/44c2fa9807944136218a0842e3051c0a379a002d

    f4fb688c-4412-4426-b4b8-421ecf27b14a

  • Source reference

    Unverified legacy reference

    URL: https://typo3.org/security/advisory/typo3-core-sa-2026-016

    f4fb688c-4412-4426-b4b8-421ecf27b14a

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.