CVE-2026-77139

Medium

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.

SeverityMedium

CVSS6.0

Exploit probability—

Product

Extension "Mask"

PublishedAug 25, 2026

First seenAug 25, 2026

Weakness typeCWE-22Path traversal CWE-73CWE-73

How to fix

Update

TYPO3 Extension "Mask"9.0.11, 8.3.12 or later

Vendor advisories

typo3.org/security/advisory/typo3-ext-sa-2026-017

Affected products

Product	Affected versions	Fixed in
TYPO3 Extension "Mask"	9.0.0 ≤ v < 9.0.11, v < 8.3.12	9.0.11, 8.3.12

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