CVE-2026-9824mediumCWE-862

CVE-2026-9824: medium-severity vulnerability in Mattermost

Remote cluster metadata enumeration via /share-channel autocomplete

Published

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13Vexday Risk Score

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

ssvc Trackcvss 4.3epss 0.3%
Mattermost versions 11.7.x <= 11.7.2, 11.6.x <= 11.6.4, 10.11.x <= 10.11.19 fail to check the manage_shared_channels permission in the /share-channel autocomplete handler, which allows an authenticated user without that permission to enumerate configured remote cluster connection metadata via slash command autocomplete.. Mattermost Advisory ID: MMSA-2026-00676
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
Affected products
Mattermost · Mattermost
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