CVE-2026-7387
Published:June 12, 2026
Updated:June 29, 2026
Mattermost versions 11.6.x <= 11.6.1, 11.5.x <= 11.5.4, 10.11.x <= 10.11.15, 10.11.x <= 10.11.16 Mattermost fails to require role-management authorization when setting the scheme_admin flag on group syncable link and patch endpoints, which allows a user with group-link permissions to escalate themselves and group members to team or channel admin via crafted API requests.. Mattermost Advisory ID: MMSA-2026-00665
Affected Packages
https://github.com/mattermost/mattermost.git (GITHUB):
Affected version(s) >=v11.6.0 <v11.6.2Fix Suggestion:
Update to version v11.6.2https://github.com/mattermost/mattermost.git (GITHUB):
Affected version(s) >=v10.11.0 <v10.11.16Fix Suggestion:
Update to version v10.11.16https://github.com/mattermost/mattermost.git (GITHUB):
Affected version(s) >=v11.5.0 <v11.5.5Fix Suggestion:
Update to version v11.5.5github.com/mattermost/mattermost (GO):
Affected version(s) >=v10.11.0 <v10.11.16Fix Suggestion:
Update to version v10.11.16github.com/mattermost/mattermost (GO):
Affected version(s) >=v11.5.0 <v11.5.5Fix Suggestion:
Update to version v11.5.5github.com/mattermost/mattermost (GO):
Affected version(s) >=v11.6.0 <v11.6.2Fix Suggestion:
Update to version v11.6.2Related Resources (1)
Do you need more information?
Contact UsCVSS v4
Base Score:
8.7
Attack Vector
NETWORK
Attack Complexity
LOW
Attack Requirements
NONE
Privileges Required
LOW
User Interaction
NONE
Vulnerable System Confidentiality
HIGH
Vulnerable System Integrity
HIGH
Vulnerable System Availability
HIGH
Subsequent System Confidentiality
NONE
Subsequent System Integrity
NONE
Subsequent System Availability
NONE
CVSS v3
Base Score:
8.8
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
HIGH
Availability
HIGH
Weakness Type (CWE)
Incorrect Authorization
EPSS
Base Score:
0.30