CVE-2026-3109lowCWE-754

CVE-2026-3109: low-severity vulnerability in Mattermost

Missing timestamp validation in Zoom webhook handler

Published

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8Vexday Risk Score

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

ssvc Trackcvss 2.2epss 0.3%
Mattermost Plugins versions <=11.4 10.11.11.0 fail to validate webhook request timestamps which allows an attacker to corrupt Zoom meeting state in Mattermost via replayed webhook requests. Mattermost Advisory ID: MMSA-2026-00584
CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:L
Affected products
Mattermost · Mattermost
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