CVE-2026-6345: Mattermost doesn't prevent disclosure of created user password

May 18, 2026 (updated June 1, 2026)

Mattermost versions 11.5.x <= 11.5.1, 10.11.x <= 10.11.13, 11.4.x <= 11.4.3 doesn’t prevent disclosure of created user password which allows a malicious attacker to impersonate a user via the use of some of those passwords.. Mattermost Advisory ID: MMSA-2026-00614

References

github.com/advisories/GHSA-wvgv-4fc3-2rcp
github.com/mattermost/mattermost/commit/3057ae7e83e9c827ce7818d67c0f3a208f0d9709
mattermost.com/security-updates
nvd.nist.gov/vuln/detail/CVE-2026-6345

Code Behaviors & Features

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