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OS Command Injection

When user input reaches a shell: separators, exfiltration, and the fix.

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Final exam

3 questions in 10 minutes, 3 to pass. Certificates require it.

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  1. 01How command injection worksshell_exec plus concatenation equals a shell for strangers.
  2. 02Lab: the helpful ping boxA diagnostic page shells out. Get it to introduce itself.
  3. 03Command injection quizThree questions on separators, blind cases, and fixes.