CVE-2026-86348mediumCWE-704

CVE-2026-86348: medium-severity vulnerability in Mattermost

MS Calendar plugin: unrecovered handler panics from malformed post-action requests could crash the plugin process

Published

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13Vexday Risk Score

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

ssvc Trackcvss 4.3epss 0.4%
Mattermost versions <=11.9 11.0.9 11.4.8 11.7.7 10.22.11.0 fail to recover from handler panics, which allows an authenticated user to crash the plugin via a post-action request with an unexpected field type.. Mattermost Advisory ID: MMSA-2026-00701
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L
Affected products
Mattermost · Mattermost
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