diff --git a/Library/Homebrew/Gemfile.lock b/Library/Homebrew/Gemfile.lock
index 854b6fdcee..9fc0ad2ea6 100644
--- a/Library/Homebrew/Gemfile.lock
+++ b/Library/Homebrew/Gemfile.lock
@@ -134,7 +134,7 @@ GEM
       rubocop-ast (>= 1.19.1, < 2.0)
       ruby-progressbar (~> 1.7)
       unicode-display_width (>= 1.4.0, < 3.0)
-    rubocop-ast (1.19.1)
+    rubocop-ast (1.21.0)
       parser (>= 3.1.1.0)
     rubocop-performance (1.14.3)
       rubocop (>= 1.7.0, < 2.0)