Search Results for: buffer overflow exploit
Root Cause Analysis – Integer Overflows
Table of ContentsForewordIntroductionAnalyzing the Crash DataIdentifying the Cause of ExceptionPage heapInitial analysisReversing the Faulty FunctionDetermining ExploitabilityChallengesPrerequisitesHeap BasicsLookaside ListsFreelistsPreventative Security MeasuresSafe-UnlinkingHeap CookiesApplication Specific ExploitationThoughts on This AttackGeneric Exploitation MethodsLookaside List OverwriteOverviewApplication Specific TechniqueWhy Not?Brett Moore: Wrecking Freelist[0] Since 2005Freelist[0] Insert AttackOverviewApplication Specific TechniqueWhy Not?Freelist[0] Searching AttackOverviewApplication Specific TechniqueWhy Not?ConclusionRecommended Reading Foreword Over the past few years, […]
Exploit writing tutorial part 11 : Heap Spraying Demystified
A lot has been said and written already about heap spraying, but most of the existing documentation and whitepapers focus on IE7 or older versions.
Although there are a number of public exploits available that target IE8, the exact technique to do so has not been really documented in detail.
Of course, you can probably derive how it works by looking at those public exploits.
With this tutorial, I’m going to provide you with a full and detailed overview on what heap spraying is, and how to use it on old and newer platforms.
I’ll start with some “ancient” techniques (or classic techniques if you will) that can be used on IE6 and IE7.
We’ll also look at heap spraying for non-browser applications.
Next, we’ll talk about precision heap spraying, which is a requirement to make DEP bypass exploits work on IE8.
I’ll finish this tutorial with sharing some of my own research on getting reliable heap spraying to work on IE9.
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Corelan Training "Corelan Live – Win32 Exploit Development Bootcamp"
Introduction Starting this year, Corelan will be teaching live Win32 exploit development classes at various security conferences. Titled “Corelan Live – Win32 Exploit Development Bootcamp“, this 2-day instructor-led course will teach everything you need to know about writing exploits for a Win32 environment and exploiting stack based vulnerabilities. During the first day, all basics about […]
Offensive Security Exploit Weekend
Introduction I’m excited and honored to be able to announce that Sud0, one of our Corelan Team members, has won the Offensive Security Exploit weekend, an exploiting exercise only available to Offensive Security certified alumni. The challenge was built around a vulnerability in Foxit Reader. Each participant was pointed to a Proof of Concept exploit, […]
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)…
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Exploiting Ken Ward Zipper : Taking advantage of payload conversion
In the article I wrote on the abysssec.com website, I explained the steps and techniques needed to build a working exploit for Ken Ward’s zipper. One of the main difficulties I had to overcome when building the exploit, was the character set limitation. I basically could only use a subset of the ascii characters (only […]
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 the application and trigger the application to run arbitrary code… code that is injected by the […]
Exploit writing tutorial part 8 : Win32 Egg Hunting
Introduction Easter is still far away, so this is probably the right time to talk about ways to hunting for eggs (so you would be prepared when the easter bunny brings you another 0day vulnerability) In the first parts of this exploit writing tutorial series, we have talked about stack based overflows and how they […]
Exploit writing tutorial part 7 : Unicode – from 0x00410041 to calc
Finally … after spending a couple of weeks working on unicode and unicode exploits, I’m glad and happy to be able to release this next article in my basic exploit writing series : writing exploits for stack based unicode buffer overflows (wow – that’s a mouthful). You may (or may not) have encountered a situation […]
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 ret overwrite or exception handler structure overwrites) are based on the fact that a reliable return […]
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