CVE-2026-10542mediumCWE-639

CVE-2026-10542: medium-severity vulnerability in Mattermost

Playbooks channel action update validation issue

Published

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13Vexday Risk Score

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

ssvc Trackcvss 5epss 0.1%
Mattermost versions 11.9.x <= 11.9.0, 11.8.x <= 11.8.4, 11.7.x <= 11.7.7, 10.11.x <= 10.11.22 fail to validate channel action ownership which allows channel managers to update actions in other channels via the channel action update endpoint.. Mattermost Advisory ID: MMSA-2026-00692
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:L
Affected products
Mattermost · Mattermost
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