Posts:

Hack Notes : ROP retn+offset and impact on stack setup

Yesterday, sickn3ss (one of the frequent visitors of the #corelan channel on freenode IRC) posted a really interesting question.

The question

While testing ROP gadgets, as part of the process of building a DEP bypass exploit for WM Downloader, Read more

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Exploit writing tutorial part 10 : Chaining DEP with ROP – the Rubik’s[TM] Cube

About 3 months after finishing my previous exploit writing related tutorial, I finally found some time and fresh energy to start writing a new article. In the previous tutorials, I have explained the basics of stack based overflows and how they can lead to arbitrary code execution. I discussed direct RET overflows, SEH based exploits, Unicode and other character restrictions, the use of debugger plugins to speed up exploit development, how to bypass common memory protection mechanisms and how to write your own shellcode. While the first tutorials were really written to learn the basics about exploit development, starting from scratch (targeting people without any knowledge about exploit development) you have most likely discovered that the more recent tutorials continue to build on those basics and require solid knowledge of asm, creative thinking, and some experience with exploit writing in general. Today's tutorial is no different. I will continue to build upon everything we have seen and learned in the previous tutorials. Today I will talk about ROP and how it can be used to bypass DEP (and ASLR)... Read more
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QuickZip Stack BOF 0day: a box of chocolates

Over the last couple of weeks, ever since I published 2 articles on the Offensive Blog, I have received many requests from people asking me if they could get a copy of those articles in pdf format.  My blog Read more

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Ken Ward Zipper exploit write-up on abysssec.com

Hi all,

I just wanted to drop a few lines to let you know that, earlier today, my exploit write-up article about this vulnerability was published on www.abysssec.com.

You can find the article here : http://www.abysssec.com/blog/2010/03/ken-ward-zipper-stack-bof-0day-a-not-so-typical-seh-exploit/

Enjoy !

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QuickZip exploit article part 2 released on OffSec Blog

Hi all.  

I just wanted to drop a quick note that I have released part 2 of the QuickZip 0day vulnerability exploit on the Offensive Security Blog just a few moments ago.  

You can find the article here.

Have fun & cheers !

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Exploit writing tutorial part 9 : Introduction to Win32 shellcoding

Over the last couple of months, I have written a set of tutorials about building exploits that target the Windows stack. One of the primary goals of anyone writing an exploit is to modify the normal execution flow of Read more

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Exploit writing tutorial part 6 : Bypassing Stack Cookies, SafeSeh, SEHOP, HW DEP and ASLR

Introduction

In all previous tutorials in this Exploit writing tutorial series, we have looked at building exploits that would work on Windows XP / 2003 server.

The success of all of these exploits (whether they are based on direct Read more

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Exploit writing tutorial part 3b : SEH Based Exploits – just another example

In the previous tutorial post, I have explained the basics of SEH based exploits. I have mentioned that in the most simple case of an SEH based exploit, the payload is structured like this :

[Junk][next SEH][SEH][Shellcode]

I Read more

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Exploit writing tutorial part 3 : SEH Based Exploits

In the first 2 parts of the exploit writing tutorial series, I have discussed how a classic stack buffer overflow works and how you can build a reliable exploit by using various techniques to jump to the shellcode.  The Read more

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Exploit writing tutorial part 2 : Stack Based Overflows – jumping to shellcode

Where do you want to jmp today ?

In one of my previous posts (part 1 of writing stack based buffer overflow exploits), I have explained the basisc about discovering a vulnerability and using that information to build a Read more

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