An unprivileged application can exploit a lack of package/signature validation in SystemUI's `RemoteQCController` when resolving a hardcode…

An unprivileged application can exploit a lack of package/signature validation in SystemUI's `RemoteQCController` when resolving a hardcoded `content://` URI. This allows the attacker to squat on a specific authority if the legitimate package is absent, inject spoofed UI elements into the trusted SystemUI Quick Controls panel, and gain a Background Activity Launch (BAL) grant from SystemUI when the user interacts with the spoofed element.