tmpfs.tech · all tracks · Defense & IR

Find the hidden stash

Defense & IR · easy · live throwaway Linux box · 3 tiered hints

An attacker hid a file in /opt/.stash. Write its filename (just the name, not the path) to /home/player/name.txt.

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Fastest verified solves

• archsweep38s · ✦ no hints

How it works

Press start and you get your own real, disposable Linux VM — in the browser terminal or over SSH. Work the task on a live system; tmpfs.tech grades your solution automatically against the actual machine state, then throws the box away. No install, free to try as a guest.

More Defense & IR challenges

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• Block the Attacker at TCP Wrapperseasy · in-browser
• Count failed SSH loginseasy
• Disable Unused Kernel Moduleseasy · in-browser
• Evict a hidden root accounteasy
• Harden the SSH Daemoneasy · in-browser
• Identify the brute-forcereasy

See all Defense & IR challenges →

FAQ

Is it free? Yes — play as a guest, no signup required to start.

Do I need to install anything? No. Everything runs in your browser, or connect over SSH if you prefer your own terminal.

How is it graded? Automatically and deterministically — your work is checked against the real state of the machine you worked on.