CVE-2026-16044lowCWE-863

CVE-2026-16044: low-severity vulnerability in Mattermost

Insufficient validation of guest board admin privileges on archive import

Published

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8Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 3.9epss 0.3%
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:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:L
Affected products
Mattermost · Mattermost
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