diff --git a/Gemfile b/Gemfile
index a19c9b1..0ce2a54 100644
--- a/Gemfile
+++ b/Gemfile
@@ -6,7 +6,7 @@ gem 'rails', '~> 5.0.0', '>= 5.0.0.1'
 # Use sqlite3 as the database for Active Record
 gem 'sqlite3'
 # 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 8988567..162b735 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -125,7 +125,7 @@ GEM
     nokogiri (1.6.8.1)
       mini_portile2 (~> 2.1.0)
     orm_adapter (0.5.0)
-    puma (3.6.0)
+    puma (3.12.6)
     pundit (1.1.0)
       activesupport (>= 3.0.0)
     rack (2.0.1)
@@ -243,7 +243,7 @@ DEPENDENCIES
   jquery-ui-rails
   listen (~> 3.0.5)
   mini_magick
-  puma (~> 3.0)
+  puma (~> 3.12)
   pundit
   rails (~> 5.0.0, >= 5.0.0.1)
   rails-assets-tether (>= 1.3.3)!