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PentesterAcademy Vulnerable Servers II Lab Write-Up | metasploit-pivoting

PentesterAcademy Vulnerable Servers II Lab Write-Up | metasploit-pivoting Lab Link : Vulnerable Servers II is a lab from PentesterAcademy, which is rated as easy. The lab topology shows two machines which means, there are two targets and the attacker has to perform pivoting in order to hack and get the flag from the target machine. First Select the nearest Server and Click on Run the lab.   Once the lab is up, a web based terminal will be opened in the Web Browser. Firstly, check the IP address of the attacking machine.  We can see that, there are two interfaces. And as per the instructions, the first target machine should be Let’s perform an Nmap scan of the target. The scan result shows that TCP port 8080 is open and is running an Apache Tomcat webserver/Coyote JSP engine 1.1. Let’s try to connect the webserver using netcat.   We can see that the Webserver is running OpenKM, a Document

Different CTF a.k.a Adana Room from TryHackMe [THM] Writeup

Room link :

Excellent room. Spend much time on Recon and Enum. The room developer has also put a sweet spot rabbit hole. The WordPress.

Different CTF Adana Room from TryHackMe [THM] Writeup

I am not making this write-up in detail. You perform the initial nmap scan, get couple of open ports and services. Then perform a dirbuster or gobuster scan. You get the secret directory. Announcement. In the Announcement directory, you can see an image and a word-list. As common with THM, we can easily assume that there might be some kind of stenography involved. And yes, but with a point. I used steghide and exif tools at first but you need to use brute-force method to crack the hidden data. Also the hint is given on the room poster. Anyway.

Different CTF Adana Room from TryHackMe [THM] Writeup
Use Stegbrute to crack the image.
Stegbrute gives an output file and its encrypted. Do a Base64 conversion to decode and here it is, the FTP credentials.
Different CTF Adana Room from TryHackMe [THM] Writeup

Decode using icyberchef. 

Different CTF Adana Room from TryHackMe [THM] Writeup

Now we have the FTP creds and let's try it.
Well, the directory structe looks like the web folder. We can upload a reverse php shell and execute from the browser directly, so that we can get the shell. Right? Well, same thoughts.

Different CTF Adana Room from TryHackMe [THM] Writeup

I uploaded the reverse shell (php) file, changed the permissions (777). Opened up the netcat listener and accessed the URL from the browser. Ummm. Nothing happens. No reverse shell.

Different CTF Adana Room from TryHackMe [THM] Writeup
Different CTF Adana Room from TryHackMe [THM] Writeup

Something is not right. Let's browse the FTP directories. Saw the wp-admin.php file that contains the configurations, downloaded to my machine and examined. Yay Yay, got another set of credentials. This time the phpadmin. okay, lets check that.

Different CTF Adana Room from TryHackMe [THM] Writeup

After we logged in to the phpmyadmin page, we can see the databases associated with the Wordpress sites. Examine the pages for important information.

Different CTF Adana Room from TryHackMe [THM] Writeup

Different CTF Adana Room from TryHackMe [THM] Writeup

Different CTF Adana Room from TryHackMe [THM] Writeup

Wow. There is an another identical website with a subdomain. So the reverse shell file that we have uploaded might be gone to the other website. After adding the subdomain to the etc/hosts file, access the website. Same right? Yes same same. Try to access the reverse shell file from the new website [subdomain.adana.thm]. There you go. We got the reverse shell. The web-flag is right in the folder. That was easy. Now hunt for the user flag.

Different CTF Adana Room from TryHackMe [THM] Writeup

After examining the home folder and the etc/passwd file, we identified the user "hakanbey". Tried the sudo -l , no permission and linpeas, not much help.
Actually got stuck. Went to the room page seeking some hints. Yes. They have mentioned sucrack in the poster. sucrack is used to crack the user password. Downloaded Sucrack from Github , tar it and transferred to the target machine. Follow the installation details of sucrack regarding the installation and usage. Also here is a reference guide on sucrack 

I used the same wordlist and tried to crack the user hakanbey. Nope. Didn't help. Some thoughts on password reuse and patterns. The FTP password of hakan begins with 123adana. So the user might be having a password in that pattern. Append 123adana to the all words in the wordfile.

sed 's/^/123adana/' /var/www/html/announcements/wordlist.txt > newlist.txt

Use that new wordlist to crack the password. And that works. We got the user credentials.

Different CTF Adana Room from TryHackMe [THM] Writeup

Switch user, and get the user flag from the home directory of hakanbey. Well done so far.

Different CTF Adana Room from TryHackMe [THM] Writeup

Now the root flag. Lets hunt for the SUIDs and there is one unusual candidate. /usr/bin/binary.
Upon examining the binary using ltrace , we got some hints. A key for executing the binary. 

Different CTF Adana Room from TryHackMe [THM] WriteupDifferent CTF Adana Room from TryHackMe [THM] Writeup

Execute, give the correct key and there we get an output. root.jpg. The hint says to use hexeditor, an offset location and use icyberchef for base85 conversion. Transfer the file to your machine using netcat or any other desired methods.

Different CTF Adana Room from TryHackMe [THM] Writeup

Use the hexeditor, look for the mentioned offset. Copy it. Convert it using icyberchef. And we get the root credentials. Go back to the target machine, switch user with the root creds and grab the root flag.

Different CTF Adana Room from TryHackMe [THM] Writeup

Spend a lot of time , especially exploring the rabbit hole. Losing the DB connections and multiple resets. However, that was funny. Kudos to the developer.

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