diff --git a/Library/Homebrew/vendor/Gemfile.lock b/Library/Homebrew/vendor/Gemfile.lock
index cbb0bd6da9..c6ab320754 100644
--- a/Library/Homebrew/vendor/Gemfile.lock
+++ b/Library/Homebrew/vendor/Gemfile.lock
@@ -43,7 +43,7 @@ GEM
     plist (3.5.0)
     powerpack (0.1.2)
     rainbow (3.0.0)
-    rubocop (0.63.1)
+    rubocop (0.64.0)
       jaro_winkler (~> 1.5.1)
       parallel (~> 1.10)
       parser (>= 2.5, != 2.5.1.1)