diff --git a/Gemfile.lock b/Gemfile.lock
index 9dac3c6..cc2a742 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -131,7 +131,7 @@ GEM
     rb-fsevent (0.11.2)
     rb-inotify (0.11.1)
       ffi (~> 1.0)
-    rdoc (6.7.0)
+    rdoc (6.8.1)
       psych (>= 4.0.0)
     regexp_parser (2.9.2)
     rexml (3.3.9)