CVE-2026-3116mediumCWE-400

CVE-2026-3116: medium-severity vulnerability in Mattermost

Improper Input Validation in Zoom Plugin Webhook Handler

Published

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13Vexday Risk Score

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

ssvc Trackcvss 4.9epss 0.4%
Mattermost Plugins versions <=11.4 11.0.4 11.1.3 11.3.2 10.11.11.0 fail to validate incoming request size which allows an authenticated attacker to cause service disruption via the webhook endpoint. Mattermost Advisory ID: MMSA-2026-00589
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H
Affected products
Mattermost · Mattermost
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