zsteg

v0.2.13zed-0xff

Walks bit planes, channels and pixel orders looking for readable payloads, reporting hits in the familiar `b1,rgb,lsb,xy` locator form and extracting them with `-E`.

Category: Data decoding, cryptanalysis & analysis
Package: zsteg
Runs on: Linux
Commands: zsteg

Scans the deterministic carrier model derived from the simulated file's own bytes. Nothing decodes a real PNG.

Install it

The scripts below install the real zed-0xff package on your own machine — read them first, and run them somewhere you are allowed to change. Inside the range, one press puts the simulated package on your next machine.

Linux installer (shell script)

install-zsteg.sh

Windows installer (PowerShell)

Install-zsteg.ps1

No native Windows build. Use a Linux host in the range, or run it under WSL.

On a range machine

Add it to your kit and every machine you launch comes with it.

On Linux

Ruby (gem)

Install Ruby and its headers
```
sudo apt install -y ruby ruby-dev
```
Install zsteg
```
sudo gem install zsteg
```

Check it worked

Confirm it landed on PATH
```
which zsteg
```
Check the version
```
zsteg --version
```
The range reports 0.2.13.

Remove it

Take it off again
```
sudo gem uninstall zsteg
```

On Windows

No native Windows build. Use a Linux host in the range, or run it under WSL.

Windows Subsystem for Linux

Install a Linux userland on the Windows host
```
wsl --install -d Ubuntu
```
The upstream project has no native Windows build; WSL is the usual way round it.
Install zsteg inside it
```
wsl sudo apt install -y zsteg
```

Inside the range

Tick it on the launch screen
Under zsteg's category on the advanced tool shelf. A lab that depends on it locks the toggle on and says why.
Or install it from a range terminal
```
sudo apt install -y zsteg
```
The simulated package manager seeds the same binaries, config and receipt the shelf toggle does.
Everything here is simulated
No software is downloaded and nothing executes — the range answers from authored fixtures.

Labs that use zsteg

No lab locks this one on yet — tick it on the launch screen and take it into any scenario.