GHSA-vg6q-84p8-qvqh
Mattermost allows a user on a remote to set their remote username prop to an arbitrary string
Packages
| Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|
| Go | github.com/mattermost/mattermost/server/v8 | >= 9.5.0, < 9.5.7 | 9.5.7 |
| Go | github.com/mattermost/mattermost/server/v8 | >= 9.7.0, < 9.7.6 | 9.7.6 |
| Go | github.com/mattermost/mattermost/server/v8 | >= 9.8.0, < 9.8.2 | 9.8.2 |
| Go | github.com/mattermost/mattermost/server/v8 | >= 9.9.0, < 9.9.1 | 9.9.1 |
Details
As written in the advisory (Markdown source, shown as plain text).
Mattermost versions 9.9.x <= 9.9.0, 9.5.x <= 9.5.6, 9.7.x <= 9.7.5, 9.8.x <= 9.8.1 fail to disallow users to set their own remote username, when shared channels were enabled, which allows a user on a remote to set their remote username prop to an arbitrary string, which would be then synced to the local server as long as the user hadn't been synced before.
References
External links from the advisory. They lead to third-party sites.