CVE-2026-77139 - Vulnerability Details - OpenCVE

The extension fails to validate a client-supplied template element key before using it to build file paths for saving and deleting Mask template files. An authenticated backend user with access to the Mask module can supply a key containing path traversal sequences to create or delete .html files outside the configured template directory.

Attack Vector Network

Attack Complexity Low

Privileges Required Low

Attack Requirements Present

User Interaction None

Vulnerable System Confidentiality Impact None

Vulnerable System Integrity Impact High

Vulnerable System Availability Impact Low

Subsequent System Confidentiality Impact None

Subsequent System Integrity Impact None

Subsequent System Availability Impact None

No CVSS v3.1

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

No EPSS score available.

Key SSVC decision points have not yet been added.

No data.

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Advisories

No advisories yet.

Fixes

Solution

No solution given by the vendor.

Workaround

No workaround given by the vendor.

References

Link	Providers
https://typo3.org/security/advisory/typo3-ext-sa-2026-017

History

Tue, 25 Aug 2026 09:15:00 +0000

Type	Values Removed	Values Added
Description		The extension fails to validate a client-supplied template element key before using it to build file paths for saving and deleting Mask template files. An authenticated backend user with access to the Mask module can supply a key containing path traversal sequences to create or delete .html files outside the configured template directory.
Title		Path Traversal in extension "Mask" (mask)
Weaknesses		CWE-22 CWE-73
References		https://typo3.org/security/advisory/typo3-ext-sa-2026-017
Metrics		cvssV4_0 `{'score': 6, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:H/VA:L/SC:N/SI:N/SA:N'}`

Projects

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MITRE

Status: PUBLISHED

Assigner: TYPO3

Published: 2026-08-25T09:00:37.199Z

Updated: 2026-08-25T09:00:37.199Z

Reserved: 2026-08-20T13:10:15.962Z

Link: CVE-2026-77139

Vulnrichment

No data.

NVD

Status : Received

Published: 2026-08-25T09:17:34.647

Modified: 2026-08-25T09:17:34.647

Link: CVE-2026-77139

Redhat

No data.

OpenCVE Enrichment

No data.

Weaknesses

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