diff --git a/Gemfile.lock b/Gemfile.lock
index 436350e..d4cf252 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -172,7 +172,7 @@ GEM
       protocol-hpack (~> 1.4)
       protocol-http (~> 0.18)
     public_suffix (4.0.6)
-    puma (4.3.8)
+    puma (4.3.9)
       nio4r (~> 2.0)
     racc (1.5.2)
     rack (2.2.3)