diff --git a/Gemfile.lock b/Gemfile.lock
index 097bcf8..1e0dcde 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -14,7 +14,7 @@ GEM
     multi_xml (0.6.0)
     mustermann (1.0.3)
     nio4r (2.5.2)
-    puma (4.2.1)
+    puma (4.3.3)
       nio4r (~> 2.0)
     rack (2.0.7)
     rack-protection (2.0.7)