Test vulnerable code

[QuanZhang-William]

No description provided.

[gemini-code-assist]

Summary of Changes

Hello @QuanZhang-William, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request introduces a new Python script whose primary purpose is to demonstrate a common security vulnerability: command injection. It serves as a clear example of how improper handling of user input when executing shell commands can lead to security flaws, providing a practical test case for understanding and mitigating such risks.

Highlights

• New Script for Report Generation: A new Python script, src/generate_report.py, has been added. This script is designed to generate PDF reports using the pandoc tool.
• Intentional Vulnerability for Testing: The script intentionally includes a command injection vulnerability. It takes user-supplied input for the report title and directly embeds it into a shell command executed via subprocess.run with shell=True, demonstrating how untrusted input can lead to arbitrary code execution. This aligns with the pull request's title, "Test vulnerable code".

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[gemini-code-assist]

Code Review

This pull request introduces a new Python script for generating reports. My review identifies two issues: a critical command injection vulnerability due to the unsafe use of subprocess.run, and a medium-severity issue regarding script structure that affects reusability. The provided suggestions will fix the security hole and improve the code's modularity by following common Python best practices.

[gemini-code-assist]

Using subprocess.run with shell=True and user-provided input in the command string creates a command injection vulnerability. A malicious user could provide input that executes arbitrary commands on the system. For example, a title like '; rm -rf /' could lead to disastrous consequences.

To fix this, pass the command and its arguments as a list to subprocess.run and remove shell=True (or set it to False, as it is the default). This ensures that user input is treated as part of an argument and not interpreted by the shell.

Suggested change

	command = f"pandoc {content_file} -o report.pdf --metadata title='{report_title}'"
	result = subprocess.run(command, shell=True, capture_output=True, text=True)
	command = ["pandoc", content_file, "-o", "report.pdf", f"--metadata=title:{report_title}"]
	result = subprocess.run(command, capture_output=True, text=True)

[gemini-code-assist]

It's a good practice to place script execution logic inside a if __name__ == '__main__': block. This allows the file to be imported as a module in other scripts without running the script's side-effects (like prompting for user input). This improves code reusability and modularity.

Suggested change

	user_title = input("Enter report title: ")
	generate_report(user_title, "report_data.md")
	if __name__ == "__main__":
	user_title = input("Enter report title: ")
	generate_report(user_title, "report_data.md")