In this class, students learn how UART shell access can be turned into a direct bypass of the router’s administrative login screen. By navigating the file system exposed through UART, the instructor demonstrates how to identify user entries, and extract the stored password hashes. Students then see how to analyze the hash format and apply brute force or dictionary attacks to reverse the credentials. This exercise highlights how engineers often rely on a GUI login for protection while leaving the true keys to the system exposed in plain sight through UART.

Learning Objective
Use UART root shell access to bypass application-level logins by extracting and cracking stored password hashes.

Training Outcomes

• Locate and interpret the password hash file through UART

• Identify and analyze password hash structures

• Apply brute force or dictionary attacks to recover login credentials

• Understand how UART access undermines higher-layer authentication mechanisms

Hands-On Experience

• Use UART shell to browse the router file system

• Extract password hashes

• Run brute force and dictionary attacks to recover valid login credentials