diff --git a/CHANGELOG.md b/CHANGELOG.md
index f00d93e..3034c1b 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,8 @@
 # Change Log
 
+## [0.6.3](https://github.com/WinRb/rubyntlm/tree/0.6.4) (2024-06-06)
+[Full Changelog](https://github.com/WinRb/rubyntlm/compare/v0.6.3...0.6.4)
+
 ## [0.6.3](https://github.com/WinRb/rubyntlm/tree/0.6.3) (2021-01-26)
 [Full Changelog](https://github.com/WinRb/rubyntlm/compare/v0.6.2...0.6.3)
 
@@ -124,4 +127,4 @@
 ## [v0.2.0](https://github.com/WinRb/rubyntlm/tree/v0.2.0) (2013-03-22)
 
 
-\* *This Change Log was automatically generated by [github_changelog_generator](https://github.com/skywinder/Github-Changelog-Generator)*
\ No newline at end of file
+\* *This Change Log was automatically generated by [github_changelog_generator](https://github.com/skywinder/Github-Changelog-Generator)*
diff --git a/lib/net/ntlm/version.rb b/lib/net/ntlm/version.rb
index b6a2dba..376bcf7 100644
--- a/lib/net/ntlm/version.rb
+++ b/lib/net/ntlm/version.rb
@@ -4,7 +4,7 @@ module NTLM
     module VERSION
       MAJOR = 0
       MINOR = 6
-      TINY  = 3
+      TINY  = 4
       STRING = [MAJOR, MINOR, TINY].join('.')
     end
   end
diff --git a/rubyntlm.gemspec b/rubyntlm.gemspec
index 8bad250..a75f322 100644
--- a/rubyntlm.gemspec
+++ b/rubyntlm.gemspec
@@ -16,7 +16,7 @@ Gem::Specification.new do |s|
   s.test_files    = s.files.grep(%r{^(test|spec|features)/})
   s.require_paths = ["lib"]
 
-  s.required_ruby_version = '>= 1.8.7'
+  s.required_ruby_version = '>= 2.6.0'
 
   s.license = 'MIT'
 
@@ -26,4 +26,6 @@ Gem::Specification.new do |s|
   s.add_development_dependency "rspec", ">= 2.11"
   s.add_development_dependency "simplecov"
   s.add_dependency "base64"
+
+  s.metadata["rubygems_mfa_required"] = "true"
 end