CVE-2025-13321: Mattermost Desktop App exposes sensitive information in its application logs

December 17, 2025 (updated December 19, 2025)

Mattermost Desktop App versions < 6.0.0 fail to sanitize sensitive information from Mattermost logs and clear data on server deletion which allows an attacker with access to the users system to gain access to potentially sensitive information via reading the application logs.

A fix is available for direct download via the Mattermost Desktop repository, but it has not been uploaded to the npm registry at time of publication.

References

github.com/advisories/GHSA-g6qx-wq5w-wr8v
github.com/mattermost/desktop/commit/722938bb6a97e8b8a5678e6858e44c4d505c08ee
github.com/mattermost/mattermost
mattermost.com/security-updates
nvd.nist.gov/vuln/detail/CVE-2025-13321

Code Behaviors & Features

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