diff --git a/Gemfile b/Gemfile
index 999432f..d969e4d 100644
--- a/Gemfile
+++ b/Gemfile
@@ -5,7 +5,7 @@ ruby "2.3.1"
 gem 'rails', '~> 5.0.0', '>= 5.0.0.1'
 gem 'pg'
 # 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 7295458..61604f5 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -158,7 +158,7 @@ GEM
       mimemagic (~> 0.3.0)
     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)
@@ -261,7 +261,7 @@ DEPENDENCIES
   paperclip
   pg
   prev-next!
-  puma (~> 3.0)
+  puma (~> 3.12)
   quill-rails5!
   railroady
   rails (~> 5.0.0, >= 5.0.0.1)