CVE-2012-5664 options hashes should only be extracted if there are ex…

…tra parameters

activerecord/lib/active_record/base.rb

@@ -1065,7 +1065,11 @@ def method_missing(method_id, *arguments, &block)
                 eowarn
             end
             if match.finder?
-              options = arguments.extract_options!
+              options = if arguments.length > attribute_names.size
+                          arguments.extract_options!
+                        else
+                          {}
+                        end
               relation = options.any? ? scoped(options) : scoped
               relation.send :find_by_attributes, match, attribute_names, *arguments
             elsif match.instantiator?

activerecord/test/cases/finder_test.rb

@@ -15,6 +15,18 @@
 class FinderTest < ActiveRecord::TestCase
   fixtures :companies, :topics, :entrants, :developers, :developers_projects, :posts, :comments, :accounts, :authors, :customers, :categories, :categorizations
 
+  def test_find_by_id_with_hash
+    assert_raises(ActiveRecord::StatementInvalid) do
+      Post.find_by_id(:limit => 1)
+    end
+  end
+
+  def test_find_by_title_and_id_with_hash
+    assert_raises(ActiveRecord::StatementInvalid) do
+      Post.find_by_title_and_id('foo', :limit => 1)
+    end
+  end
+
   def test_find
     assert_equal(topics(:first).title, Topic.find(1).title)
   end