diff --git a/test_app/Gemfile b/test_app/Gemfile
index 84bcb04..e7e9f5c 100644
--- a/test_app/Gemfile
+++ b/test_app/Gemfile
@@ -6,7 +6,7 @@ gem 'rails', '~> 5.0.0', '>= 5.0.0.1'
 # Use sqlite3 as the database for Active Record
 
 # Use Puma as the app server
-gem 'puma', '~> 3.0'
+gem 'puma', '~> 3.12'
 # Use SCSS for stylesheets
 gem 'bootstrap-sass', '~> 3.3.6'
 gem 'sass-rails', '~> 5.0'
diff --git a/test_app/Gemfile.lock b/test_app/Gemfile.lock
index c786a16..c276d43 100644
--- a/test_app/Gemfile.lock
+++ b/test_app/Gemfile.lock
@@ -90,7 +90,7 @@ GEM
       pkg-config (~> 1.1.7)
     pg (0.18.4)
     pkg-config (1.1.7)
-    puma (3.6.0)
+    puma (3.12.6)
     rack (2.0.1)
     rack-test (0.6.3)
       rack (>= 1.0)
@@ -179,7 +179,7 @@ DEPENDENCIES
   jquery-rails
   listen (~> 3.0.5)
   pg
-  puma (~> 3.0)
+  puma (~> 3.12)
   rails (~> 5.0.0, >= 5.0.0.1)
   rails_12factor
   sass-rails (~> 5.0)