diff --git a/Gemfile b/Gemfile
index 07f9cec..b79eb46 100644
--- a/Gemfile
+++ b/Gemfile
@@ -13,7 +13,7 @@ git_source(:github) do |repo_name|
 end
 
 gem "nio4r", "= 2.5.2"
-gem "puma", "= 4.3.5"
+gem "puma", "4.3.11"
 
 gem "bagit"
 gem "bcrypt", "~> 3.1.7"
diff --git a/Gemfile.lock b/Gemfile.lock
index 2e76cc1..fc7eccc 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -160,7 +160,7 @@ GEM
       pry (~> 0.10)
     psych (3.1.0)
     public_suffix (3.0.2)
-    puma (4.3.5)
+    puma (4.3.11)
       nio4r (~> 2.0)
     rack (2.2.3)
     rack-cors (1.0.5)
@@ -325,7 +325,7 @@ DEPENDENCIES
   nio4r (= 2.5.2)
   pry
   pry-byebug
-  puma (= 4.3.5)
+  puma (= 4.3.11)
   rack-cors
   rails (~> 5.1.0)
   rails-controller-testing