An access control vulnerability was discovered in Grafana OSS where an Organization administrator could permanently delete the Server admin…

An access control vulnerability was discovered in Grafana OSS where an Organization administrator could permanently delete the Server administrator account. This vulnerability exists in the DELETE /api/org/users/ endpoint.

The vulnerability can be exploited when:

1. An Organization administrator exists

2. The Server administrator is either:

- Not part of any organization, or
- Part of the same organization as the Organization administrator
Impact:

- Organization administrators can permanently delete Server administrator accounts

- If the only Server administrator is deleted, the Grafana instance becomes unmanageable

- No super-user permissions remain in the system

- Affects all users, organizations, and teams managed in the instance

The vulnerability is particularly serious as it can lead to a complete loss of administrative control over the Grafana instance.