Medium · published August 12, 2026
Admidio is an open-source user management solution. Prior to version 5.0.10, `modules/sso/clients.php` validates an `adm_csrf_token` on every state-changing branch except `enable`. The `enable` case loads the SAML or OIDC client by UUID, calls `$client->enable($enabled)`, and persists the new state with no token check. Because the action is reachable via plain GET parameters, a third-party page can trick an authenticated administrator into disabling (or silently re-enabling) any configured SAML or OIDC client. Disabling an SSO client breaks every downstream relying-party application that authenticates through it. Version 5.0.10 contains a fix.