diff --git a/Gemfile.lock b/Gemfile.lock
index edb784d..b13491f 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -7,11 +7,10 @@ PATH
 GEM
   remote: https://rubygems.org/
   specs:
-    json (1.8.3)
+    json (2.5.1)
     minitest (5.8.0)
     rake (10.2.2)
-    rdoc (4.1.1)
-      json (~> 1.4)
+    rdoc (6.3.1)
 
 PLATFORMS
   ruby