diff --git a/carbon_off/Gemfile b/carbon_off/Gemfile
index 4f7ae57..7e14904 100644
--- a/carbon_off/Gemfile
+++ b/carbon_off/Gemfile
@@ -9,7 +9,7 @@ gem 'rails', '~> 5.2.3'
 # Use sqlite3 as the database for Active Record
 gem 'sqlite3'
 # Use Puma as the app server
-gem 'puma', '~> 3.11'
+gem 'puma', '~> 3.12'
 # Use SCSS for stylesheets
 gem 'sass-rails', '~> 5.0'
 # Use Uglifier as compressor for JavaScript assets
diff --git a/carbon_off/Gemfile.lock b/carbon_off/Gemfile.lock
index 2d028dc..7843428 100644
--- a/carbon_off/Gemfile.lock
+++ b/carbon_off/Gemfile.lock
@@ -110,7 +110,7 @@ GEM
     nokogiri (1.10.3)
       mini_portile2 (~> 2.4.0)
     public_suffix (3.1.1)
-    puma (3.12.1)
+    puma (3.12.3)
     rack (2.0.7)
     rack-proxy (0.6.5)
       rack
@@ -215,7 +215,7 @@ DEPENDENCIES
   coffee-rails (~> 4.2)
   jbuilder (~> 2.5)
   listen (>= 3.0.5, < 3.2)
-  puma (~> 3.11)
+  puma (~> 3.12)
   rails (~> 5.2.3)
   react-rails
   sass-rails (~> 5.0)