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 hadnt been synced before.
The product does not restrict or incorrectly restricts access to a resource from an unauthorized actor.
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Mattermost_server | Mattermost | 9.5.0 (including) | 9.5.7 (excluding) |
| Mattermost_server | Mattermost | 9.7.0 (including) | 9.7.6 (excluding) |
| Mattermost_server | Mattermost | 9.8.0 (including) | 9.8.2 (excluding) |
| Mattermost_server | Mattermost | 9.9.0 (including) | 9.9.0 (including) |
Access control involves the use of several protection mechanisms such as:
When any mechanism is not applied or otherwise fails, attackers can compromise the security of the product by gaining privileges, reading sensitive information, executing commands, evading detection, etc. There are two distinct behaviors that can introduce access control weaknesses: