diff --git a/programmers_preferences_backend/Gemfile b/programmers_preferences_backend/Gemfile
index 4868ed9..1413c90 100644
--- a/programmers_preferences_backend/Gemfile
+++ b/programmers_preferences_backend/Gemfile
@@ -8,7 +8,7 @@ gem 'rails', '~> 6.0.2', '>= 6.0.2.1'
 # Use postgresql as the database for Active Record
 gem 'pg', '>= 0.18', '< 2.0'
 # Use Puma as the app server
-gem 'puma', '~> 4.1'
+gem 'puma', '~> 4.3'
 # Use SCSS for stylesheets
 gem 'sass-rails', '>= 6'
 # Transpile app-like JavaScript. Read more: https://github.com/rails/webpacker
diff --git a/programmers_preferences_backend/Gemfile.lock b/programmers_preferences_backend/Gemfile.lock
index d6ab7aa..249244d 100644
--- a/programmers_preferences_backend/Gemfile.lock
+++ b/programmers_preferences_backend/Gemfile.lock
@@ -93,7 +93,7 @@ GEM
     nokogiri (1.10.9)
       mini_portile2 (~> 2.4.0)
     pg (1.2.3)
-    puma (4.3.3)
+    puma (4.3.5)
       nio4r (~> 2.0)
     rack (2.2.2)
     rack-cors (1.1.1)
@@ -202,7 +202,7 @@ DEPENDENCIES
   jbuilder (~> 2.7)
   listen (>= 3.0.5, < 3.2)
   pg (>= 0.18, < 2.0)
-  puma (~> 4.1)
+  puma (~> 4.3)
   rack-cors
   rails (~> 6.0.2, >= 6.0.2.1)
   rspec-rails