diff --git a/docs/Gemfile.lock b/docs/Gemfile.lock
index 113f1f9..5b8fa7f 100644
--- a/docs/Gemfile.lock
+++ b/docs/Gemfile.lock
@@ -228,7 +228,7 @@ GEM
     rb-fsevent (0.11.2)
     rb-inotify (0.10.1)
       ffi (~> 1.0)
-    rexml (3.2.5)
+    rexml (3.3.9)
     rouge (3.26.0)
     ruby2_keywords (0.0.5)
     rubyzip (2.3.2)