Class: Brakeman::CheckModelAttributes

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

Overview

Check if mass assignment is used with models which inherit from ActiveRecord::Base.

If tracker.options is true (default), all models which do not use attr_accessible will be reported in a single warning

Constant Summary

Constants inherited from BaseCheck

BaseCheck::CONFIDENCE

Constants included from Util

Util::ALL_PARAMETERS, Util::COOKIES, Util::COOKIES_SEXP, Util::PARAMETERS, Util::PARAMS_SEXP, Util::PATH_PARAMETERS, Util::QUERY_PARAMETERS, Util::REQUEST_ENV, Util::REQUEST_PARAMETERS, Util::REQUEST_PARAMS, Util::SESSION, Util::SESSION_SEXP

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_call, #process_cookies, #process_default, #process_if, #process_params, #process_string_interp

Methods included from Util

#array?, #block?, #call?, #camelize, #contains_class?, #context_for, #cookies?, #false?, #file_by_name, #file_for, #github_url, #hash?, #hash_access, #hash_insert, #hash_iterate, #integer?, #make_call, #node_type?, #number?, #params?, #pluralize, #regexp?, #relative_path, #request_env?, #request_value?, #result?, #set_env_defaults, #sexp?, #string?, #symbol?, #table_to_csv, #template_path_to_name, #true?, #truncate_table, #underscore

Methods included from ProcessorHelper

#class_name, #process_all, #process_all!, #process_call_args, #process_class, #process_module

Methods inherited from SexpProcessor

#error_handler, #in_context, #initialize, #process, #process_dummy, #scope

Constructor Details

This class inherits a constructor from Brakeman::BaseCheck

Instance Method Details

#check_for_attr_protected_bypassObject


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# File 'lib/brakeman/checks/check_model_attributes.rb', line 92

def check_for_attr_protected_bypass
  upgrade_version = case
                    when version_between?("2.0.0", "2.3.16")
                      "2.3.17"
                    when version_between?("3.0.0", "3.0.99")
                      "3.2.11"
                    when version_between?("3.1.0", "3.1.10")
                      "3.1.11"
                    when version_between?("3.2.0", "3.2.11")
                      "3.2.12"
                    else
                      nil
                    end

  if upgrade_version
    message = "attr_protected is bypassable in #{tracker.config[:rails_version]}, use attr_accessible or upgrade to #{upgrade_version}"
    confidence = CONFIDENCE[:high]
    link = "https://groups.google.com/d/topic/rubyonrails-security/AFBKNY7VSH8/discussion"
  else
    message = "attr_accessible is recommended over attr_protected"
    confidence = CONFIDENCE[:med]
    link = nil
  end

  return message, confidence, link
end

#check_modelsObject


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# File 'lib/brakeman/checks/check_model_attributes.rb', line 84

def check_models
  tracker.models.each do |name, model|
    if unprotected_model? model
      yield name, model
    end
  end
end

#run_checkObject


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# File 'lib/brakeman/checks/check_model_attributes.rb', line 13

def run_check
  return if mass_assign_disabled?

  #Roll warnings into one warning for all models
  if tracker.options[:collapse_mass_assignment]
    no_accessible_names = []
    protected_names = []

    check_models do |name, model|
      if model[:options][:attr_protected].nil?
        no_accessible_names << name.to_s
      elsif not tracker.options[:ignore_attr_protected]
        protected_names << name.to_s
      end
    end

    unless no_accessible_names.empty?
      warn :model => no_accessible_names.sort.join(", "),
        :warning_type => "Attribute Restriction",
        :warning_code => :no_attr_accessible,
        :message => "Mass assignment is not restricted using attr_accessible",
        :confidence => CONFIDENCE[:high]
    end

    unless protected_names.empty?
      message, confidence, link = check_for_attr_protected_bypass

      if link
        warning_code = :CVE_2013_0276
      else
        warning_code = :attr_protected_used
      end

      warn :model => protected_names.sort.join(", "),
        :warning_type => "Attribute Restriction",
        :warning_code => warning_code,
        :message => message,
        :confidence => confidence,
        :link => link
    end
  else #Output one warning per model

    check_models do |name, model|
      if model[:options][:attr_protected].nil?
        warn :model => name,
          :file => model[:files].first,
          :warning_type => "Attribute Restriction",
          :warning_code => :no_attr_accessible,
          :message => "Mass assignment is not restricted using attr_accessible",
          :confidence => CONFIDENCE[:high]
      elsif not tracker.options[:ignore_attr_protected]
        message, confidence, link = check_for_attr_protected_bypass

        if link
          warning_code = :CVE_2013_0276
        else
          warning_code = :attr_protected_used
        end

        warn :model => name,
          :file => model[:files].first,
          :line => model[:options][:attr_protected].first.line,
          :warning_type => "Attribute Restriction",
          :warning_code => warning_code,
          :message => message,
          :confidence => confidence
      end
    end
  end
end