stack overflow code in c for writing exploit

Question

I am attempting to launch a shell in my Linux environment (BT3) but it keeps seg faulting. The method that I'm using is out of The Shellcoder's HandBook. Note that all of this is straight out of the text.

For more reference: http://www.backtrack-linux.org/forums/old-pentesting/15508-stuck-eip-buffer-overflow.html

@Als Sorry, I hope I'm not being too aggressive in suggesting edits to this question? ("hi i m facing a problem plz help me" doesn't seem necessary...) — Chris Frederick, Jul 15 '11 at 18:58
@Chris: No that seems logical, I approved your edit, It needs one more approval to be accepted, someone will approve soon. — Alok Save, Jul 15 '11 at 19:01

score 3 · Answer 1 · answered Jul 15 '11 at 18:56

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Many buffer overflow exploits have been fixed in modern operating system patches. It's likely you're seg faulting because the operating system is detecting a buffer overrun and killing your process.

answered Jul 15 '11 at 18:56

Rich

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score 1 · Answer 2 · answered Jul 15 '11 at 19:10

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If you're running on a modern kernel then your application is segfaulting because exploiting EIP is easily detectable by the OS. When EIP gets changed or overrun the OS has mechanisms in place to check whether the location EIP is pointing is valid in the virtual memory area. In the case of that exploit that check would fail and the OS would send a SIGKILL or SIGSEGV to your application to prevent any harm from being done.

answered Jul 15 '11 at 19:10

Jesus Ramos

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you can't disble it unless you find the relevant code in the operating system and remove it which is a bad idea – Jesus Ramos Jul 16 '11 at 04:19
i have disabled this but still not able to do it – bhavis Jul 17 '11 at 12:45
I doubt that you've disabled all the places where EIP overflows in the kernel are detected, this is also not the place to ask about how to exploit systems or certain things hence why your question was closed – Jesus Ramos Jul 17 '11 at 13:13

stack overflow code in c for writing exploit

2 Answers2