CVE-2025-27933: Mattermost allows members with permission to convert public channels to private and convert private to public

March 21, 2025

Mattermost versions 10.4.x <= 10.4.2, 10.3.x <= 10.3.3, 9.11.x <= 9.11.8 fail to to enforce channel conversion restrictions, which allows members with permission to convert public channels to private ones to also convert private ones to public.

References

github.com/advisories/GHSA-h5v9-xw2g-7hrq
github.com/mattermost/mattermost
mattermost.com/security-updates
nvd.nist.gov/vuln/detail/CVE-2025-27933

Code Behaviors & Features

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