Class: Brakeman::CheckUnsafeReflectionMethods

Inherits:
BaseCheck show all
Defined in:
lib/brakeman/checks/check_unsafe_reflection_methods.rb

Constant Summary

Constants inherited from BaseCheck

BaseCheck::CONFIDENCE

Constants included from Util

Util::ALL_COOKIES, Util::ALL_PARAMETERS, Util::COOKIES, Util::COOKIES_SEXP, Util::DIR_CONST, Util::LITERALS, Util::PARAMETERS, Util::PARAMS_SEXP, Util::PATH_PARAMETERS, Util::QUERY_PARAMETERS, Util::REQUEST_COOKIES, Util::REQUEST_ENV, Util::REQUEST_PARAMETERS, Util::REQUEST_PARAMS, Util::REQUEST_REQUEST_PARAMETERS, Util::SAFE_LITERAL, Util::SESSION, Util::SESSION_SEXP, Util::SIMPLE_LITERALS

Constants inherited from SexpProcessor

SexpProcessor::VERSION

Instance Attribute Summary

Attributes inherited from BaseCheck

#tracker, #warnings

Attributes inherited from SexpProcessor

#context, #env, #expected

Instance Method Summary collapse

Methods inherited from BaseCheck

#add_result, inherited, #initialize, #process_array, #process_call, #process_cookies, #process_default, #process_dstr, #process_if, #process_params

Methods included from Messages

#msg, #msg_code, #msg_cve, #msg_file, #msg_input, #msg_lit, #msg_plain, #msg_version

Methods included from Util

#all_literals?, #array?, #block?, #call?, #camelize, #class_name, #constant?, #contains_class?, #cookies?, #dir_glob?, #false?, #hash?, #hash_access, #hash_insert, #hash_iterate, #hash_values, #integer?, #kwsplat?, #literal?, #make_call, #node_type?, #number?, #params?, #pluralize, #rails_version, #recurse_check?, #regexp?, #remove_kwsplat, #request_headers?, #request_value?, #result?, #safe_literal, #safe_literal?, #safe_literal_target?, #set_env_defaults, #sexp?, #simple_literal?, #string?, #string_interp?, #symbol?, #template_path_to_name, #true?, #underscore

Methods included from ProcessorHelper

#current_file, #process_all, #process_all!, #process_call_args, #process_call_defn?, #process_class, #process_module

Methods inherited from SexpProcessor

#in_context, #initialize, #process, processors, #scope

Constructor Details

This class inherits a constructor from Brakeman::BaseCheck

Instance Method Details

#check_method ⇒ Object 



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# File 'lib/brakeman/checks/check_unsafe_reflection_methods.rb', line 14

def check_method
  tracker.find_call(method: :method, nested: true).each do |result|
    argument = result[:call].first_arg

    if user_input = include_user_input?(argument)
      warn_unsafe_reflection(result, user_input)
    end
  end
end

#check_tap ⇒ Object 



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# File 'lib/brakeman/checks/check_unsafe_reflection_methods.rb', line 24

def check_tap
  tracker.find_call(method: :tap, nested: true).each do |result|
    argument = result[:call].first_arg

    # Argument is passed like a.tap(&argument)
    if node_type? argument, :block_pass
      argument = argument.value
    end

    if user_input = include_user_input?(argument)
      warn_unsafe_reflection(result, user_input)
    end
  end
end

#check_to_proc ⇒ Object 



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# File 'lib/brakeman/checks/check_unsafe_reflection_methods.rb', line 39

def check_to_proc
  tracker.find_call(method: :to_proc, nested: true).each do |result|
    target = result[:call].target

    if user_input = include_user_input?(target)
      warn_unsafe_reflection(result, user_input)
    end
  end
end

#run_check ⇒ Object 



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# File 'lib/brakeman/checks/check_unsafe_reflection_methods.rb', line 8

def run_check
  check_method
  check_tap
  check_to_proc
end

#warn_unsafe_reflection(result, input) ⇒ Object 



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# File 'lib/brakeman/checks/check_unsafe_reflection_methods.rb', line 49

def warn_unsafe_reflection result, input
  return unless original? result
  method = result[:call].method

  confidence = if input.type == :params
    :high
  else
    :medium
  end

  message = msg("Unsafe reflection method ", msg_code(method), " called with ", msg_input(input))

  warn :result => result,
    :warning_type => "Remote Code Execution",
    :warning_code => :unsafe_method_reflection,
    :message => message,
    :user_input => input,
    :confidence => confidence,
    :cwe_id => [470]
end