diff --git a/Gemfile b/Gemfile
index b571ea8..4bbe6c6 100644
--- a/Gemfile
+++ b/Gemfile
@@ -11,7 +11,7 @@ gem 'rails', '~> 5.0.1'
 # Use postgresql as the database for Active Record
 gem 'pg', '~> 0.18'
 # Use Puma as the app server
-gem 'puma', '~> 3.0'
+gem 'puma', '~> 3.12'
 # Use SCSS for stylesheets
 gem 'sass-rails', '~> 5.0'
 # Use Uglifier as compressor for JavaScript assets
diff --git a/Gemfile.lock b/Gemfile.lock
index 6408a48..325e980 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -124,7 +124,7 @@ GEM
       slop (~> 3.4)
     pry-rails (0.3.4)
       pry (>= 0.9.10)
-    puma (3.7.0)
+    puma (3.12.4)
     rack (2.0.1)
     rack-test (0.6.3)
       rack (>= 1.0)
@@ -218,7 +218,7 @@ DEPENDENCIES
   paperclip (~> 5.0.0)
   pg (~> 0.18)
   pry-rails
-  puma (~> 3.0)
+  puma (~> 3.12)
   rails (~> 5.0.1)
   rails_12factor
   sass-rails (~> 5.0)