GHSA-x883-2vmg-xwf7: 
vulnerability analysis and mitigation

The vulnerability (GHSA-x883-2vmg-xwf7) affects Authelia's group changes functionality in versions 4.37.0 to 4.38.0. Under specific conditions involving the file authentication backend with watch option enabled and configured refresh_interval, changes to user groups may not be reflected in access control as expected (GitHub Advisory).

The issue occurs when all of the following conditions are met: the file authentication backend is being used, the watch option is set to true, the refresh_interval is configured to a non-disabled value, and users' groups are adjusted by an administrator. The vulnerability has a CVSS score of 1.6 (Low) with metrics indicating physical attack vector, high attack complexity, high privileges required, and required user interaction (GitHub Advisory).

When the vulnerability conditions are met, administrators may find that group changes are not taken into account by access control for longer than expected periods. The impact is limited as it cannot affect unauthenticated users, configurations using the LDAP Backend, or be triggered by users or third parties (GitHub Advisory).

The vulnerability requires physical access, high attack complexity, and high privileges with user interaction. It cannot be directly or indirectly caused by users or third parties, significantly limiting its exploitability (GitHub Advisory).

The issue has been patched in version 4.38.0. For affected versions, users can work around the issue by ensuring they restart between user database changes. The fix ensures that user details are updated regardless of backend, addressing the oversight in previous functionality which made refreshing ineffectual prior to v4.37.0 (GitHub Advisory).