diff --git a/Gemfile.lock b/Gemfile.lock
index 5718f65..6d20d0b 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -46,7 +46,7 @@ GEM
     psych (3.1.0)
     rack (2.0.8)
     rake (13.0.1)
-    rdoc (6.2.1)
+    rdoc (6.3.2)
     semver2 (3.4.2)
     test-unit (3.3.4)
       power_assert