diff --git a/project_backend/Gemfile b/project_backend/Gemfile
index 60672cd..d53a41e 100644
--- a/project_backend/Gemfile
+++ b/project_backend/Gemfile
@@ -8,7 +8,7 @@ gem 'rails', '~> 6.0.2', '>= 6.0.2.2'
 # Use mysql as the database for Active Record
 gem 'mysql2', '>= 0.4.4'
 # Use Puma as the app server
-gem 'puma', '~> 4.1'
+gem 'puma', '~> 4.3'
 # Build JSON APIs with ease. Read more: https://github.com/rails/jbuilder
 # gem 'jbuilder', '~> 2.7'
 # Use Redis adapter to run Action Cable in production
diff --git a/project_backend/Gemfile.lock b/project_backend/Gemfile.lock
index 0d2f9f5..98f2732 100644
--- a/project_backend/Gemfile.lock
+++ b/project_backend/Gemfile.lock
@@ -108,7 +108,9 @@ GEM
     marcel (0.3.3)
       mimemagic (~> 0.3.2)
     method_source (1.0.0)
-    mimemagic (0.3.4)
+    mimemagic (0.3.10)
+      nokogiri (~> 1)
+      rake
     mini_mime (1.0.2)
     mini_portile2 (2.4.0)
     minitest (5.14.0)
@@ -116,12 +118,12 @@ GEM
     msgpack (1.3.3-x64-mingw32)
     mysql2 (0.5.3)
     mysql2 (0.5.3-x64-mingw32)
-    nio4r (2.5.2)
+    nio4r (2.5.8)
     nokogiri (1.10.9)
       mini_portile2 (~> 2.4.0)
     nokogiri (1.10.9-x64-mingw32)
       mini_portile2 (~> 2.4.0)
-    puma (4.3.3)
+    puma (4.3.12)
       nio4r (~> 2.0)
     rack (2.2.2)
     rack-cors (1.1.1)
@@ -215,7 +217,7 @@ DEPENDENCIES
   kaminari
   listen (>= 3.0.5, < 3.2)
   mysql2 (>= 0.4.4)
-  puma (~> 4.1)
+  puma (~> 4.3)
   rack-cors
   rails (~> 6.0.2, >= 6.0.2.2)
   rspec-rails