diff --git a/Gemfile.lock b/Gemfile.lock
index 0316759..c66b4a1 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -1,7 +1,7 @@
 GEM
   remote: https://rubygems.org/
   specs:
-    json (2.7.1)
+    json (2.9.1)
     mustermann (3.0.0)
       ruby2_keywords (~> 0.0.1)
     nio4r (2.7.0)