Medium severity · published Mar 21, 2025
CVE-2025-27933
Unauthorized Private-to-Public Channel Conversion
4.3
CVSS
0.2%
EPSS
No
On KEV
Description
Mattermost versions 10.4.x <= 10.4.2, 10.3.x <= 10.3.3, 9.11.x <= 9.11.8 fail to fail to enforce channel conversion restrictions, which allows members with permission to convert public channels to private ones to also convert private ones to public
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 11% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
MA
Mattermost · Mattermost
10.4.0 through 10.4.2; 10.3.0 through 10.3.3; 9.11.0 through 9.11.8 · source: vendor
MS
Mattermost Server · Mattermost
9.11.0 before 9.11.9; 10.3.0 before 10.3.4; 10.4.0 before 10.4.3 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2025-27933
CVE.org
https://www.cve.org/CVERecord?id=CVE-2025-27933
Vendor Advisory
https://mattermost.com/security-updates
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