diff --git a/config.rb b/config.rb
index 02f1924..f77dd03 100644
--- a/config.rb
+++ b/config.rb
@@ -5,8 +5,8 @@
 
 GITHUB_URL  = "https://github.com/xord/cruby"
 
-RUBY_URL    = 'https://cache.ruby-lang.org/pub/ruby/2.3/ruby-2.3.8.tar.gz'
-RUBY_SHA256 = 'b5016d61440e939045d4e22979e04708ed6c8e1c52e7edb2553cf40b73c59abf'
+RUBY_URL    = 'https://cache.ruby-lang.org/pub/ruby/2.4/ruby-2.4.5.tar.gz'
+RUBY_SHA256 = '6737741ae6ffa61174c8a3dcdd8ba92bc38827827ab1d7ea1ec78bc3cefc5198'
 
 
 module CRuby