medium5.4
CVE-2025-27933
Mattermost allows members with permission to convert public channels to private and convert private to public
Impact
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.
Affected packages
| Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|
| go | github.com/mattermost/mattermost/server/v8 | >= 10.4.0, < 10.4.3 | 10.4.3 |
| go | github.com/mattermost/mattermost-server | < 9.11.9 | 9.11.9 |
Affected products
| Vendor | Product | Affected versions |
|---|---|---|
| Mattermost | Mattermost Server | from 9.11.0 before 9.11.9 from 10.3.0 before 10.3.4 from 10.4.0 before 10.4.3 |