diff --git a/stub/api/Gemfile.lock b/stub/api/Gemfile.lock
index 0abba6a2..e8dc05a3 100644
--- a/stub/api/Gemfile.lock
+++ b/stub/api/Gemfile.lock
@@ -15,7 +15,7 @@ GEM
     docile (1.3.2)
     i18n (1.6.0)
       concurrent-ruby (~> 1.0)
-    json (2.1.0)
+    json (2.3.1)
     minitest (5.11.3)
     mustermann (1.0.3)
     rack (2.0.6)