Description
Mattermost versions 10.5.x <= 10.5.5, 9.11.x <= 9.11.15, 10.8.x <= 10.8.0, 10.7.x <= 10.7.2, 10.6.x <= 10.6.5 fail to properly enforce channel member management permissions when adding participants to playbook runs. This allows authenticated users with member-level permissions to bypass system admin restrictions and add or remove users to/from private channels via the playbook run participants feature, even when the 'Manage Members' permission has been explicitly removed. This can lead to unauthorized access to sensitive channel content and allow guest users to gain channel management privileges.
References (1)
Core 1
Core References
Vendor Advisory
https://mattermost.com/security-updates
Scores
CVSS v3
5.4
EPSS
0.0021
EPSS Percentile
43.7%
Attack Vector
NETWORK
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N
CISA SSVC
Vulnrichment
Exploitation
none
Automatable
no
Technical Impact
partial
Details
CWE
CWE-863
Status
published
Products (4)
mattermost/mattermost
0 - 8.0.0-20250513065225-4ae5d647fb88Go
mattermost/mattermost-server
0 - 0.0.0-20250513065225-4ae5d647fb88Go
mattermost/mattermost_server
10.8.0 (4 CPE variants)
mattermost/mattermost_server
9.11.0 - 9.11.16
Published
Jun 30, 2025
Tracked Since
Feb 18, 2026