diff --git a/Gemfile.lock b/Gemfile.lock
index 59ecd06505..0fdb8a90a7 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -128,8 +128,8 @@ GEM
       concurrent-ruby (~> 1.0)
     io-event (1.7.3)
     json (2.8.2)
-    kramdown (2.4.0)
-      rexml
+    kramdown (2.5.1)
+      rexml (>= 3.3.9)
     listen (3.9.0)
       rb-fsevent (~> 0.10, >= 0.10.3)
       rb-inotify (~> 0.9, >= 0.9.10)