CVE-2026-9820lowCWE-862

CVE-2026-9820: low-severity vulnerability in Mattermost

Mattermost schemes teams endpoint exposes private team invite IDs

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8Vexday Risk Score

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

ssvc Trackcvss 3.8epss 0.3%
Mattermost versions 11.7.x <= 11.7.2, 10.11.x <= 10.11.19 fail to sanitize team objects returned by the scheme teams endpoint, which allows a user with the User Manager role to obtain invite links for private teams and use them to join or share access to those teams via the scheme teams API endpoint.. Mattermost Advisory ID: MMSA-2026-00671
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:L/A:N
Affected products
Mattermost · Mattermost
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