class TaintedLove::Replacer::ReplaceKernel

Public Instance Methods

open(*args, &block) click to toggle source
# File lib/tainted_love/replacer/replace_kernel.rb, line 21
def open(*args, &block)
  first = args.first
  return_value = _tainted_love_original_open(*args, &block)

  if first.tainted?
    return_value.taint

    TaintedLove.report(
      :ReplaceKernel,
      first,
      [:rce],
      'Kernel#open begins with "|" and uses tainted input'
    ) if first.is_a?(String) && first[0] == '|'
  else
    return_value.untaint
  end

  return_value
end
replace!() click to toggle source
# File lib/tainted_love/replacer/replace_kernel.rb, line 6
def replace!
  %i[eval system `].each do |method|
    TaintedLove.proxy_method(Kernel, method) do |_, *args|
      TaintedLove.report(
        :ReplaceKernel,
        args.first,
        [:rce],
        "Kernel##{method} execution using tainted input"
      ) if args.first&.tainted?
    end
  end

  Kernel.class_eval do
    alias_method :_tainted_love_original_open, :open

    def open(*args, &block)
      first = args.first
      return_value = _tainted_love_original_open(*args, &block)

      if first.tainted?
        return_value.taint

        TaintedLove.report(
          :ReplaceKernel,
          first,
          [:rce],
          'Kernel#open begins with "|" and uses tainted input'
        ) if first.is_a?(String) && first[0] == '|'
      else
        return_value.untaint
      end

      return_value
    end
  end
end