76 lines
2.0 KiB
Plaintext
76 lines
2.0 KiB
Plaintext
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#!/usr/bin/env ruby
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$LOAD_PATH << File.join(File.dirname(__FILE__), '..', 'lib')
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require 'optparse'
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require 'safe_yaml/load'
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options = {}
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option_parser = OptionParser.new do |opts|
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opts.banner = "Usage: safe_yaml [options]"
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opts.on("-f", "--file=<path>", "Parse the given YAML file, dump the result to STDOUT") do |file|
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options[:file] = file
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end
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opts.on("--libyaml-check", "Check for libyaml vulnerability CVE-2014-2525 on your system") do
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options[:libyaml_check] = true
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end
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end
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option_parser.parse!
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def report_libyaml_ok
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puts "\e[32mGood news! You definitely have either a patched or up-to-date libyaml version :)\e[39m"
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end
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def check_for_overflow_bug
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YAML.load("--- !#{'%20' * 100}")
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report_libyaml_ok
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end
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def perform_libyaml_check(force=false)
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unless SafeYAML::LibyamlChecker.libyaml_version_ok?
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warn <<-EOM.gsub(/^ +/, ' ')
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\e[33mSafeYAML Warning\e[39m
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\e[33m----------------\e[39m
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\e[31mYou may have an outdated version of libyaml (#{SafeYAML::LibyamlChecker::LIBYAML_VERSION}) installed on your system.\e[39m
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Prior to 0.1.6, libyaml is vulnerable to a heap overflow exploit from malicious YAML payloads.
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For more info, see:
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https://www.ruby-lang.org/en/news/2014/03/29/heap-overflow-in-yaml-uri-escape-parsing-cve-2014-2525/
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EOM
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end
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puts <<-EOM.gsub(/^ +/, ' ')
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Hit Enter to check if your version of libyaml is vulnerable. This will run a test \e[31mwhich may crash\e[39m
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\e[31mthe current process\e[39m. If it does, your system is vulnerable and you should do something about it.
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Type "nm" and hit Enter if you don't want to run the check.
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See the project wiki for more info:
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https://github.com/dtao/safe_yaml/wiki/The-libyaml-vulnerability
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EOM
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if STDIN.readline.chomp("\n") != 'nm'
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check_for_overflow_bug
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end
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end
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if options[:libyaml_check]
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perform_libyaml_check(options[:force_libyaml_check])
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elsif options[:file]
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yaml = File.read(options[:file])
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result = SafeYAML.load(yaml)
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puts result.inspect
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else
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puts option_parser.help
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end
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