CVE-2026-3524highCWE-862

CVE-2026-3524: high-severity vulnerability in Mattermost

Authorization Bypass in Mattermost Legal Hold Plugin Due to Missing Return After Permission Check

Published · Updated

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21Vexday Risk Score

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

ssvc Trackcvss 8.3epss 0.4%
Mattermost Plugin Legal Hold versions <=1.1.4 fail to halt request processing after a failed authorization check in ServeHTTP which allows an authenticated attacker to access, create, download, and delete legal hold data via crafted API requests to the plugin's endpoints. Mattermost Advisory ID: MMSA-2026-00621
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Affected products
Mattermost · Mattermost
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