OpenAdmin HTB Writeup

User.txt

From port scanning two ports are open 80 and 22. I brute force the root directory / using gobuster and find out /ona/ visiting this /ona/ I see it is openadmin. I search using searchsploit and found out a shell script which gives me rce. Using dos2unix I convert this script to unix format to prevent errors. Using the script I can run commands. I use wget and download a php reverse shell to the box. Then I run the script using php, and get a interactive shell. I look for configuration file to find possible passwords. After a little I find one at /var/www/ona/local and then use that password to su as jimmy(found on /etc/passwd). As jimmy user I can list all files inside internal folder because it’s owned by jimmy. I find some php files there. index.php, main.php and logout.php. Inside index.php a function checks if the user is jimmy and the password is same as a sha512sum of the password we give and if succeded we get ssh private key for joanna user. I see if I can find the password on hashes.org and I found it to be Revealed. Now all I need is to access the website from my machine and then submit it. I run netstat -alnp and see that the site is on port 52846. I create a ssh key pair on my machine and then transfer the public key to .ssh/authorized_keys and ssh into the box. then using ENTER and ~C and then enter -L 9001:localhost:52846. Now on my host I visit http://localhost:52846 and using the form I submit the credentials and after I receive the ssh private key. I use ssh2john and rockyou.txt as wordlist, I crack the private key using john. Using the private key and the password I can now ssh as joanna, and get user.txt.


root.txt

I type sudo -l and find out that I can run /bin/nano /opt/priv on gtfo bins I found how I can get a shell from when I am inside nano. I run sudo -u root /bin/nano /opt/priv and then use

1
2
^R^X
reset; sh 1>&0 2>&0

Now I am root.!


OpenAdmin HTB Writeup
http://3rg1s.com/2020/05/02/2020-05-02-OpenAdmin/
Author
3rg1s
Posted on
May 2, 2020
Licensed under