CVE-2026-6347
Mattermost doesn't sanitize sensitive configuration fields in the Mattermost Calls plugin
7.6
HIGH
CVSS 3.1
EPSS 0.05%
Description
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
How to fix CVE-2026-6347
To remediate CVE-2026-6347, upgrade the affected package to a fixed version below.
- —upgrade to 1.12.0-rc2 or later
- —upgrade to 11.5.2 or later
Is CVE-2026-6347 being exploited?
Low — EPSS is 0.1%, meaning exploitation activity has not been observed at scale.
Affected packages (2)
- from 0, < 1.12.0-rc2
- >= 11.5.0, < 11.5.2
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 3.1 | HIGH7.6 | CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:N/A:L |