diff --git a/Library/Homebrew/Gemfile.lock b/Library/Homebrew/Gemfile.lock
index b42571e4ed..4755a39fdd 100644
--- a/Library/Homebrew/Gemfile.lock
+++ b/Library/Homebrew/Gemfile.lock
@@ -166,7 +166,9 @@ GEM
 
 PLATFORMS
   aarch64-linux
-  universal-darwin
+  arm-linux
+  arm64-darwin
+  x86_64-darwin
   x86_64-linux
 
 DEPENDENCIES
@@ -218,4 +220,4 @@ RUBY VERSION
    ruby 3.4.5p51
 
 BUNDLED WITH
-   2.6.9
+   2.6.8
diff --git a/Library/Homebrew/utils/gems.rb b/Library/Homebrew/utils/gems.rb
index aea750a9ae..b29dcfca9d 100644
--- a/Library/Homebrew/utils/gems.rb
+++ b/Library/Homebrew/utils/gems.rb
@@ -10,7 +10,7 @@ Homebrew::FastBootRequire.from_rubylibdir("English")
 module Homebrew
   # Keep in sync with the `Gemfile.lock`'s BUNDLED WITH.
   # After updating this, run `brew vendor-gems --update=--bundler`.
-  HOMEBREW_BUNDLER_VERSION = "2.6.9"
+  HOMEBREW_BUNDLER_VERSION = "2.6.8" # Pinned to <2.6.9 until Ruby 3.5.
 
   # Bump this whenever a committed vendored gem is later added to or exclusion removed from gitignore.
   # This will trigger it to reinstall properly if `brew install-bundler-gems` needs it.