Whizarre

Exposure of privileged Inter-Process Communication (IPC) functionality allows a local, low-privileged attacker to replace the application UI or settings with attacker-controlled content. This is possible if the attacker can modify application launch parameters and persuade a user to start the application. Successful exploitation may lead to the disclosure of OAuth authentication tokens, the execution of locally accessible programs, or the unauthorized modification of application-generated configuration files.

Missing authentication in the local .NET backend (Fiddler.WebUi) allows a local unauthenticated attacker to mint OAuth tokens and read the machine-in-the-middle root certificate. This is achieved through an unauthenticated localhost HTTP and SignalR RPC channel. SignalR is a library that simplifies adding real-time web functionality to applications.