Description
Mattermost versions 11.10.x <= 11.10.0, 11.7.x <= 11.7.9, 11.9.x <= 11.9.1, 11.8.x <= 11.8.5 fail to enforce DM/GM check on server side which allows an authenticated user to quarantine a post belonging to DM or GM via direct API call.. Mattermost Advisory ID: MMSA-2026-00756
Affected products
mattermost: mattermost server
References1
- mattermost.com/security-updates Vendor Advisory
Metrics
- CVSS 3.1
-
6.4
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:L/A:L - EPSS — exploit probability
- 0% percentile: 4 · as of 10 November 2026
- CWE
- CWE-862
Could this be exploited in your environment?
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