diff --git a/CHANGELOG.md b/CHANGELOG.md
index 3f037d1..d0dc9ce 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -5,7 +5,12 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 
 ## [Unreleased]
 
-N/A
+### Added
+- Added Ruby 4.0.5, which fixes [CVE-2026-46727](https://www.ruby-lang.org/en/news/2026/05/20/getaddrinfo-cve-2026-46727/) - https://www.ruby-lang.org/en/news/2026/05/20/ruby-4-0-5-released/
+
+### Changed
+- Updated Bundler to `4.0.12` (from `4.0.11`), https://github.com/rubygems/rubygems/blob/bundler-v4.0.12/bundler/CHANGELOG.md
+- Updated Rubygems to `4.0.12` (from `4.0.11`), https://github.com/rubygems/rubygems/blob/v4.0.12/CHANGELOG.md
 
 ## [9044] 2026-05-16
 
diff --git a/tools/vars.rb b/tools/vars.rb
index 96c60b3..37f1d6e 100644
--- a/tools/vars.rb
+++ b/tools/vars.rb
@@ -16,8 +16,8 @@ def initialize(repo_owner, repo_name, version, rubygems_version, bundler_version
 repo_name   = 'grubruby-jemalloc'
 env_version = ENV['VERSION'] || ENV.fetch('BUILDKITE_TAG') { raise 'env VERSION= or BUILDKITE_TAG= must be set' }
 version     = env_version.delete_prefix('v').to_i
-rubygems    = '4.0.11'
-bundler     = '4.0.11'
+rubygems    = '4.0.12'
+bundler     = '4.0.12'
 
 @grubruby = Grubruby.new(repo_owner, repo_name, version, rubygems, bundler)
 
@@ -62,5 +62,6 @@ def initialize(repo_owner, repo_name, version, rubygems_version, bundler_version
   ['4.0.1', '0531fe57dfdb56bf591620d2450642ea0e0964f3512a6ebee7dc9305de69395f', 'rails70'],
   ['4.0.2', '4618db85bb9ec04d8152d0099db488694a3d3c4f52106625e4ad547f1318db87', 'rails70'],
   ['4.0.3', '22cf6005d25bbe496b5ebe9224d63a1aaabfbfe02591bb5d612517c5a7836f29', 'rails70'],
-  ['4.0.4', '6ff9d2d6e75f5a6f997222ecc45f79209d663737eceb3689d1f42ab952673fb7', 'rails70']
+  ['4.0.4', '6ff9d2d6e75f5a6f997222ecc45f79209d663737eceb3689d1f42ab952673fb7', 'rails70'],
+  ['4.0.5', '5dc5521ea54c726e6cc10b1b5a0f4004b27b482e61c04c99aed79315e30895e5', 'rails70']
 ].reverse!