CVE-2026-16044

MEDIUM CVSS 5.4 View on NVD ↗

Description

Mattermost versions 11.7.x <= 11.7.6, 10.11.x <= 10.11.21 fail to prevent guest users from receiving Board Admin privileges during board archive import which allows a board member to escalate a guest user to Board Admin via importing a crafted .boardarchive file. Mattermost Advisory ID: MMSA-2026-00672

CVSS Vector

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:L

References

https://mattermost.com/security-updates

Published: Aug 17, 2026 15:16 UTC Modified: Aug 17, 2026 16:16 UTC