Mattermost RestrictSystemAdmin Bypass Vulnerability in Versions 10.5.x and 9.11.x

A vulnerability exists in Mattermost versions 10.5.x through 10.5.3 and 9.11.x through 9.11.11, where the application fails to properly validate the RestrictSystemAdmin setting for users without access to ExperimentalSettings. This flaw allows a System Manager to access ExperimentSettings when RestrictSystemAdmin is enabled, potentially leading to unauthorized changes or access via the System Console.

Impact

Exploitation of this vulnerability could allow unauthorized access to ExperimentalSettings, enabling a System Manager to bypass restrictions and potentially manipulate settings or configurations that should be off-limits.