xiaonux

Real Debian Linux in your browser. Nothing to install.

A full Linux machine runs inside this tab, on your computer. Practise the shell, run Python, inspect a suspicious file. Reset it whenever you like.

First start downloads about 17 MB. After that it starts in under a second.

GuidesCommands typed for you, checked when they run

Learn Unix

Files, pipes, permissions and processes, one command at a time.
Python & packages

Python 3 with pip. numpy, pandas and more install without internet.
Security lab

Upload a file and take it apart with file, strings, yara and strace.

Runs in this tab, not on a server
Your files stay in this browser
Internet is off unless you turn it on
Reset any time

xiaonux Starting…

Guide

Press Ctrl+Shift+G to move between the terminal and this guide.

Internet for the machine

The machine has no internet until you choose a way in. Everything that works offline (the shell, Python, the bundled packages and tools) needs nothing here.

Connection Off Nothing leaves this tab. This computer Through the small xiaonux-net helper. Fast; any https site. Relay Through our free relay. pip, apt and GitHub only; slower, with a daily limit.

Get xiaonux-net

It shares your computer's internet with this tab only: web ports 80 and 443, never your local network. Run it, and it opens this page already paired.

Start and stop

Windows: Start: open xiaonux-net from the Start menu. A window opens; keep it open while you use the machine.
macOS: Start: unzip, then double-click xiaonux-net. It runs in a Terminal window; keep it open.
Linux: Start: tar xzf xiaonux-net-*.tar.gz && ./xiaonux-net in a terminal, and leave it running.
Stop: Press Ctrl+C in its window, or close the window. It doesn't install a service and doesn't start on its own again; run it the next time you want internet here.

The helper isn't code-signed yet

Your system will warn the first time. Check the SHA-256 above against the file, then:

Windows: SmartScreen: choose More info, then Run anyway.
macOS: Right-click the app, choose Open, then Open again. Or run xattr -d com.apple.quarantine xiaonux-net.
Linux: No warning. If it won't run, make it executable: chmod +x xiaonux-net.

What's isolated

Programs in this machine never run on your computer's processor. They run on an emulated RISC-V processor, inside WebAssembly, inside your browser's tab sandbox. The machine can't see your files or devices; it only gets what you upload.

What you can do with a suspicious file

Static analysis of any file from any system: file, strings, xxd, objdump, readelf, yara, binwalk, pefile.
Read and run scripts: shell, Python, Perl.
Run and trace RISC-V Linux programs with strace, ltrace and gdb.

What it isn't

Windows, x86 and ARM programs don't run here.
It's not a hardened malware lab. With the internet on, anything you run can reach the internet from your IP address.
Don't put passwords or secrets in the machine. Follow the law and your course's rules.

Uploads land in /root/uploads and are never marked executable. Reset deletes everything.

Real Debian Linux in your browser. Nothing to install.

Learn Unix

Python & packages

Security lab