CVE-2026-20796
low-risk
Published 2026-02-13
Mattermost versions 10.11.x <= 10.11.9 fail to properly validate channel membership at the time of data retrieval which allows a deactivated user to learn team names they should not have access to via a race condition in the /common_teams API endpoint.. Mattermost Advisory ID: MMSA-2025-00549
Do I need to act?
-
0.01% chance of exploitation
EPSS score — low exploit probability
-
Not on CISA KEV list
No confirmed active exploitation reported to CISA
?
Patch status unknown
Check vendor advisories for fix availability and mitigation guidance
3
CVSS 3.1/10
Low
NETWORK
/ HIGH complexity
Affected Products (1)
Affected Vendors
References (1)
Vendor Advisory
https://mattermost.com/security-updates
16
/ 100
low-risk
Severity
11/34 · Low
Exploitability
0/34 · Minimal
Exposure
5/34 · Minimal