Description
Mattermost versions 10.10.x <= 10.10.1 fail to properly sanitize user data during shared channel membership synchronization, which allows malicious or compromised remote clusters to access sensitive user information via unsanitized user objects. This vulnerability affects Mattermost Server instances with shared channels enabled.
References (1)
Core 1
Core References
Vendor Advisory
https://mattermost.com/security-updates
Scores
CVSS v3
6.5
EPSS
0.0005
EPSS Percentile
14.5%
Attack Vector
NETWORK
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:N
CISA SSVC
Vulnrichment
Exploitation
none
Automatable
no
Technical Impact
total
Details
CWE
CWE-862
Status
published
Products (3)
mattermost/mattermost
0 - 8.0.0-20250729073403-517ae758cd02Go
mattermost/mattermost-server
10.10.0 - 10.10.2Go
mattermost/mattermost_server
10.10.0 - 10.10.2
Published
Sep 15, 2025
Tracked Since
Feb 18, 2026