CVE-2026-18795: mattermost mattermost_server

CVSS 6.4 (medium) · published 2026-10-16

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 (NVD): mattermost mattermost_server

Fixed in (NVD): 11.7.10, 11.8.6, 11.9.2

Weakness: CWE-862

Source: NVD CVE-2026-18795

References

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