CVE-2025-11777lowCWE-863

CVE-2025-11777: low-severity vulnerability in Mattermost

Cross-team channel membership access

Published

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8Vexday Risk Score

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

ssvc Trackcvss 3.1epss 0.2%
Mattermost versions 10.11.x <= 10.11.3, 10.5.x <= 10.5.11 fail to properly validate team membership permissions in the Add Channel Member API which allows users from one team to access user metadata and channel membership information from other teams via the API endpoint
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:N/A:N
Affected products
Mattermost · Mattermost
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