I am taking the Penetration Testing with Backtrack class from offensive-security.com and am working on a buffer overflow exploit for Ability Server. I can successfully over write EIP and jump to my shellcode. However, when I start going through the shellcode in the debugger, it breaks from the shellcode. I am almost 100% sure I have eliminated bad characters.I have even compared the shellcode before I sent it to the shellcode in the debugger after I have sent it and they are the identical.
I apologize for having to post the pictures via imgur album. Since I am new to stackoverflow.com, they won't allow me to post picture until I get some street cred.
Picture are here in the buffer overflow album. (The only album) http://edwardmcfellon.imgur.com/
{Picture 1}Here, I have a break point set at EIP. All is good so far.
{Picture 2}I let the program continue and it jumps to my shell code. All is still good.
{Picture 3}When the program executes POP EBX, my shellcode breaks and this is my problem.
{Picture 4}This is where the it ends up after breaking.
Any help would be appreciated. FYI I am very new to writing buffer overflows and am looking to understand why this is happening and how to prevent it in the future. Thanks in advance.
