diff --git a/Gemfile.lock b/Gemfile.lock
index 9f30684..f9b741b 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -42,7 +42,7 @@ GEM
     ast (2.4.2)
     builder (3.3.0)
     coderay (1.1.3)
-    concurrent-ruby (1.3.4)
+    concurrent-ruby (1.3.7)
     crass (1.0.6)
     date (3.5.1)
     diff-lcs (1.5.0)