CVE-2026-77139

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.

References

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