diff --git a/Gemfile.lock b/Gemfile.lock
index 0cf8c77b47642277978d8ac99c35731d40d996ef..4806c2fc44001dc3cd6dbcc91d49bf0be81e7f4c 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -93,7 +93,7 @@ GEM
     nokogiri (1.8.0)
       mini_portile2 (~> 2.2.0)
     public_suffix (2.0.5)
-    puma (3.9.1)
+    puma (3.12.0)
     rack (2.0.3)
     rack-protection (2.0.0)
       rack