Medium severity · published Jun 20, 2025
CVE-2025-3227
Unauthorized channel member management through playbook runs
4.3
CVSS
0.2%
EPSS
No
On KEV
Description
Mattermost versions 10.5.x <= 10.5.5, 9.11.x <= 9.11.15, 10.8.x <= 10.8.0, 10.7.x <= 10.7.2, 10.6.x <= 10.6.5 fail to properly enforce channel member management permissions in playbook runs, allowing authenticated users without the 'Manage Channel Members' permission to add or remove users from public and private channels by manipulating playbook run participants when the run is linked to a channel.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
None
Integrity
Low
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 16% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
MA
Mattermost · Mattermost
10.5.0 through 10.5.5; 9.11.0 through 9.11.15; 10.8.0; 10.7.0 through 10.7.2; 10.6.0 through 10.6.5 · source: vendor
MS
Mattermost Server · Mattermost
9.11.0 before 9.11.16; 10.5.0 before 10.5.6; 10.6.0 before 10.6.6; 10.7.0 before 10.7.3; 10.8.0; 10.8.0; +2 more · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2025-3227
CVE.org
https://www.cve.org/CVERecord?id=CVE-2025-3227
Vendor Advisory
https://mattermost.com/security-updates
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