Guest user can add unauthorized team users to private channels
8Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 3.1epss 0.3%
exploitation probability
0.3%top 74% of all CVEs
observed exploitation
nono source reports it
Mattermost versions 10.5.x <= 10.5.10, 10.11.x <= 10.11.2 fail to properly validate guest user permissions when adding channel members which allows guest users to add any team members to their private channels via the `/api/v4/channels/{channel_id}/members` endpoint
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:N/A:N
Affected products
Mattermost · MattermostReferences
https://mattermost.com/security-updates