CVE-2026-93847lowCWE-863

CVE-2026-93847: low-severity vulnerability in Mattermost

Improper post type validation on scheduled post endpoints

Published · Updated

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8Vexday Risk Score

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

ssvc Trackcvss 3.5epss 0.2%
Mattermost versions 11.7.x <= 11.7.10 fail to validate reserved system post types on the scheduled post creation and publication paths which allows an authenticated channel member to publish messages rendering as trusted system events via the scheduled post endpoint.. Mattermost Advisory ID: MMSA-2026-00732
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:N
Affected products
Mattermost · Mattermost
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