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sudo ruby shell

Offensive Lab · medium · solved in-browser (no VM needed) · 3 tiered hints

Your own disposable practice box. sudo -l shows a NOPASSWD rule for /usr/bin/ruby. ruby evaluates inline code with -e and inherits root from sudo. Write /home/player/ans.txt with a single command that runs ruby through sudo with a -e program that uses exec to launch /bin/sh or /bin/bash. (Authored config, graded structurally — the engine isn't run here.)

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Open the challenge and an in-page editor appears — write your answer and tmpfs.tech grades it server-side against the same checks a real box would run. No VM, no install, no signup needed to try.

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FAQ

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How is it graded? Automatically and deterministically — your work is checked against the exact rules the live box would apply.