diff --git a/Gemfile.lock b/Gemfile.lock
index 1f0a198..9ef1924 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -60,7 +60,7 @@ GEM
       pry (~> 0.13.0)
     public_suffix (5.0.4)
     rainbow (3.0.0)
-    rdoc (6.3.1)
+    rdoc (6.3.4.1)
     regexp_parser (1.7.1)
     rexml (3.2.5)
     rspec (3.9.0)