The processor architecture of most PCs and servers, including the 386/486/Pentium/… (IA-32) 32-bit family and the amd64 64-bit family. Most x86 processors are made by Intel or AMD.

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3
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2answers
56 views

Exploit a buffer overflow without SIGSEGV

For my studies I try to create a payload so that it overflows the buffer and calls a "secret" function called "target" This is the code I use for testing on an i686 #include "stdio.h" #include ...
1
vote
1answer
61 views

Is using IsBadReadPtr and IsBadWritePtr considered to be insecure?

I am auditing (reverse engineering) an x86 C++ application without source code. Static analysis revealed that the application is using the IsBadReadPtr and IsBadWritePtr Win32 functions in almost ALL ...
3
votes
1answer
83 views

Defeating ROP attacks in x86

Most defense techniques against ROP revolves around randomization, such as ASLR. If I mark all regions of memory, other than the code segment, non-executable, will this defeat ROP?
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votes
0answers
47 views

CPU instruction encoding on x86 that is free from ROP attacks

x86 has a dense instruction encoding, and thus enables ROP attacks. Are there any CPU instruction encoding schemes that are free from these attacks?
2
votes
1answer
70 views

Defeating code injection attacks in x86

In x86 systems, there are three requirements for a code injection attack to work: write attack payload to memory attack payload to be executable divert control-flow to payload How can we prevent ...
6
votes
1answer
285 views

Return oriented programming without int 0x80

I have a program with a stack based buffer overflow. It is running PIE with ASLR and DEP, however there is a section of executable code that is at a fixed location. However, this region does not ...
0
votes
0answers
243 views

Stack buffer overflow: Is compiler changing variables order, preventing me to overwrite EIP properly?

I am learning about stack buffer overflow. A little info about my target: A x86 little endian intel-based computer, with a target compiled with TCC Compiler with no protections of any kind running on ...
1
vote
2answers
846 views

Program exiting after executing int 0x80 instruction when running shellcode

In school I was given an assignment to perform a buffer overflow, which would execute some shellcode and open a new shell. After a bit of fiddling the buffer overflow succeeded, and when I ran the ...
11
votes
4answers
2k views

Adding 65K buffer to protect from buffer overflows?

If you had a very complex and important function in C that you wanted to protect, would it be worth it to put a 65K buffer at the top of the stack to protect from buffer overflows? You would put your ...
15
votes
1answer
3k views

Return-oriented programming: how to find a stack pivot

I have a program with a heap overflow. It contains some code that is not randomized (is not using ASLR). I want to do a return-oriented programming exploit. Since this is a heap overflow, the first ...
4
votes
1answer
834 views

Occurence of ROP gadget

I'm researching various buffer overflow techniques, one I encounter and is pretty interested in the moment is Return Oriented Programming (ROP), and the use of small groups of instructions known as ...
8
votes
1answer
758 views

Better way to import Win32 APIs from injected shellcode

I'm injecting native x86 code into a .NET application, via a TLS callback in the binary image. Unfortunately, .NET executables only import mscorlib.dll within the PE, and have kernel32.dll mapped ...
5
votes
1answer
517 views

Hardware enforced DEP on different CPUs

Are there any differences how hardware DEP is implemented on CPUs from different manufacturers (Intel, AMD, nVidia, Texas,...)? Are there any significant differences how hardware DEP works on x86 ...
3
votes
2answers
991 views

Where can I find information about how to implement Intel embedded AES256 encryption?

I heard this can really speed up encryption performance, but I can't find any good information about how to implement it.