CVE-2026-6347
Published:May 18, 2026
Updated:September 25, 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
Affected Packages
https://github.com/mattermost/mattermost-plugin-calls.git (GITHUB):
Affected version(s) >=v1.0.0 <v1.11.3Fix Suggestion:
Update to version v1.11.3github.com/mattermost/mattermost-server (GO):
Affected version(s) >=v11.4.0 <v11.4.4Fix Suggestion:
Update to version v11.4.4github.com/mattermost/mattermost-plugin-calls (GO):
Affected version(s) >=server/public/v0.0.1 <v1.12.0-rc2Fix Suggestion:
Update to version v1.12.0-rc2github.com/mattermost/mattermost-server (GO):
Affected version(s) >=v11.5.0 <v11.5.2Fix Suggestion:
Update to version v11.5.2github.com/mattermost/mattermost-server (GO):
Affected version(s) >=v10.11.0 <v10.11.14Fix Suggestion:
Update to version v10.11.14github.com/mattermost/mattermost-plugin-calls (GO):
Affected version(s) >=v1.0.0 <v1.11.3Fix Suggestion:
Update to version v1.11.3Related Resources (6)
Do you need more information?
Contact UsCVSS v4
Base Score:
8.3
Attack Vector
NETWORK
Attack Complexity
LOW
Attack Requirements
NONE
Privileges Required
HIGH
User Interaction
NONE
Vulnerable System Confidentiality
HIGH
Vulnerable System Integrity
NONE
Vulnerable System Availability
LOW
Subsequent System Confidentiality
HIGH
Subsequent System Integrity
NONE
Subsequent System Availability
LOW
CVSS v3
Base Score:
7.6
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
HIGH
User Interaction
NONE
Scope
CHANGED
Confidentiality
HIGH
Integrity
NONE
Availability
LOW
Weakness Type (CWE)
Exposure of Sensitive Information to an Unauthorized Actor
EPSS
Base Score:
0.43