CVE-2026-6347: Mattermost doesn't sanitize sensitive configuration fields in the Mattermost Calls plugin

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 fail to sanitize sensitive configuration fields in the Mattermost Calls plugin which allows an attacker with access to a support packet to obtain TURN server credentials via the plaintext values present in the exported plugin configuration.. Mattermost Advisory ID: MMSA-2026-00605

References

github.com/advisories/GHSA-82j6-4fq7-fx62
github.com/mattermost/mattermost-plugin-calls/commit/d48893c8558e5a61f5fdd188bbee5ec7cb73887b
mattermost.com/security-updates
nvd.nist.gov/vuln/detail/CVE-2026-6347

Code Behaviors & Features

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