metasploit-framework/tools/halflm_second.rb

114 lines
2.6 KiB
Ruby
Executable File

#!/usr/bin/env ruby
#
# This script cracks a half-lm challenge/response hash that uses a
# a static challenge key. The idea is you use rainbow tables to
# crack the first 7 chars and this script to complete a few remaining.
# If the password is longer than 10 characters, this script will fail.
#
msfbase = File.symlink?(__FILE__) ? File.readlink(__FILE__) : __FILE__
$:.unshift(File.join(File.dirname(msfbase), '..', 'lib'))
require 'rex'
def usage
$stderr.puts("\n" + " Usage: #{$0} <options>\n" + $args.usage)
exit
end
def try(word)
buf = ::Rex::Proto::SMB::Crypt.lanman_des(word, "\x11\x22\x33\x44\x55\x66\x77\x88")
buf.unpack("H*")[0]
end
hash = pass = nil
$args = Rex::Parser::Arguments.new(
"-n" => [ true, "The encypted LM hash to crack" ],
"-p" => [ true, "The decrypted LANMAN password for bytes 1-7" ],
"-h" => [ false, "Display this help information" ])
$args.parse(ARGV) { |opt, idx, val|
case opt
when "-n"
hash = val
when "-p"
pass = val
when "-h"
usage
else
usage
end
}
if (not (hash and pass))
usage
end
if(hash.length != 48)
$stderr.puts "[*] LANMAN should be exactly 48 bytes of hexadecimal"
exit
end
if(pass.length != 7)
$stderr.puts "[*] Cracked LANMAN password should be exactly 7 characters"
exit
end
pass = pass.upcase
hash = hash.downcase
cset = [*(1..255)].pack("C*").upcase.unpack("C*").uniq
stime = Time.now.to_f
puts "[*] Trying one character..."
0.upto(cset.length-1) do |c1|
test = pass + cset[c1].chr
if(try(test) == hash)
puts "[*] Cracked: #{test}"
exit
end
end
etime = Time.now.to_f - stime
puts "[*] Trying two characters (eta: #{etime * cset.length} seconds)..."
0.upto(cset.length-1) do |c1|
0.upto(cset.length-1) do |c2|
test = pass + cset[c1].chr + cset[c2].chr
if(try(test) == hash)
puts "[*] Cracked: #{test}"
exit
end
end
end
puts "[*] Trying three characters (eta: #{etime * cset.length * cset.length} seconds)..."
0.upto(cset.length-1) do |c1|
0.upto(cset.length-1) do |c2|
0.upto(cset.length-1) do |c3|
test = pass + cset[c1].chr + cset[c2].chr + cset[c3].chr
if(try(test) == hash)
puts "[*] Cracked: #{test}"
exit
end
end
end
end
puts "[*] Trying four characters (eta: #{etime * cset.length * cset.length * cset.length} seconds)..."
0.upto(cset.length-1) do |c1|
0.upto(cset.length-1) do |c2|
0.upto(cset.length-1) do |c3|
0.upto(cset.length-1) do |c4|
test = pass + cset[c1].chr + cset[c2].chr + cset[c3].chr + cset[c4].chr
if(try(test) == hash)
puts "[*] Cracked: #{test}"
exit
end
end
end
end
end