diff --git a/Library/Homebrew/Gemfile.lock b/Library/Homebrew/Gemfile.lock
index 74824866de..917271ed76 100644
--- a/Library/Homebrew/Gemfile.lock
+++ b/Library/Homebrew/Gemfile.lock
@@ -168,4 +168,4 @@ DEPENDENCIES
   tapioca
 
 BUNDLED WITH
-   1.17.3
+   1.17.2
diff --git a/Library/Homebrew/utils/gems.rb b/Library/Homebrew/utils/gems.rb
index 0a98b06728..8fba9b3096 100644
--- a/Library/Homebrew/utils/gems.rb
+++ b/Library/Homebrew/utils/gems.rb
@@ -8,7 +8,7 @@ require "English"
 
 module Homebrew
   # Keep in sync with the Gemfile.lock's BUNDLED WITH.
-  HOMEBREW_BUNDLER_VERSION = "1.17.3"
+  HOMEBREW_BUNDLER_VERSION = "1.17.2"
 
   module_function