CVE-2026-16044
Published:August 17, 2026
Updated:September 01, 2026
Mattermost versions 11.7.x <= 11.7.6, 10.11.x <= 10.11.21 fail to prevent guest users from receiving Board Admin privileges during board archive import which allows a board member to escalate a guest user to Board Admin via importing a crafted .boardarchive file. Mattermost Advisory ID: MMSA-2026-00672
Affected Packages
https://github.com/mattermost/mattermost-plugin-boards.git (GITHUB):
Affected version(s) >=v9.0.0 <v9.2.6Fix Suggestion:
Update to version v9.2.6github.com/mattermost/mattermost (GO):
Affected version(s) >=v11.7.0 <v11.7.7Fix Suggestion:
Update to version v11.7.7github.com/mattermost/mattermost (GO):
Affected version(s) >=v10.11.0 <v10.11.22Fix Suggestion:
Update to version v10.11.22Related Resources (3)
Do you need more information?
Contact UsCVSS v4
Base Score:
5.3
Attack Vector
NETWORK
Attack Complexity
LOW
Attack Requirements
NONE
Privileges Required
LOW
User Interaction
NONE
Vulnerable System Confidentiality
NONE
Vulnerable System Integrity
LOW
Vulnerable System Availability
LOW
Subsequent System Confidentiality
NONE
Subsequent System Integrity
NONE
Subsequent System Availability
NONE
CVSS v3
Base Score:
5.4
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
LOW
Availability
LOW
Weakness Type (CWE)
Incorrect Authorization
EPSS
Base Score:
0.17