CVE-2026-8821
Mattermost versions 11.9.x <= 11.9.0, 11.8.x <= 11.8.4, 11.7.x <= 11.7.7, 10.11.x <= 10.11.22 fail to validate channel member-management permission during playbook run creation, allowing an authenticated channel member to add an arbitrary user to a restricted channel via the run owner field.. Mattermost Advisory ID: MMSA-2026-00677
- CVSS 3.1
- 7.1
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:N - EPSS
- 0.3% chance of exploitation in the next 30 days; higher than 21% of CVEs (scores of 2026-10-25)
- CWE
- CWE-862
- Published
- Modified
- Record from
- the NVD, synced
Affected
- mattermost:mattermost_server