UnoPim versions before 2.0.1 and 2.1.1 trust all connecting clients as proxies and honor the X-Forwarded-Host header without validation, allowing unauthenticated attackers to inject arbitrary origins into admin layout pages. Attackers can set X-Forwarded-Host to redirect JavaScript asset loading to their server, and when responses are cached by shared proxies, subsequent administrators execute attacker-supplied code in their authenticated sessions.