diff --git a/Gemfile.lock b/Gemfile.lock
index 8fa4d3e..97f577a 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -39,7 +39,7 @@ GEM
       ruby_process
       tpool
       wref (>= 0.0.6)
-    json (2.19.3)
+    json (2.21.1)
     knjrbfw (0.0.114)
       datet
       http2