Course

This exercise focuses on a Ruby application where the `eval` function is improperly used, leading to code injection vulnerabilities. The application, running in development mode, reveals detailed error messages that help us understand the flaw. By injecting a double quote into the `username` parameter, we can break out of the string context and concatenate commands, ultimately achieving code execution on the server.

The lab demonstrates the importance of avoiding the use of `eval` due to its inherent risks. It guides you through the process of constructing a payload to exploit the vulnerability, emphasizing the steps required to manipulate the input and execute arbitrary commands. This exercise is crucial for understanding the dangers of dynamic code evaluation and reinforces the best practices for secure coding in Ruby applications.