diff --git a/Gemfile b/Gemfile
index c5f05e9b8..84a8b8ae4 100644
--- a/Gemfile
+++ b/Gemfile
@@ -28,7 +28,7 @@ gem 'loog', '0.3.1'
 gem 'minitest', '5.18.1', require: false
 gem 'minitest-reporters', '1.6.0', require: false
 gem 'pgtk', '0.8.1'
-gem 'rack', '2.2.6.4'
+gem 'rack', '2.2.8'
 gem 'rack-ssl', '1.4.1'
 gem 'rack-test', '2.1.0'
 gem 'rake', '13.0.6', require: false
diff --git a/Gemfile.lock b/Gemfile.lock
index be43de3d5..81078a73d 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -131,7 +131,7 @@ GEM
     psych (5.1.2)
       stringio
     racc (1.7.3)
-    rack (2.2.6.4)
+    rack (2.2.8)
     rack-protection (3.0.6)
       rack
     rack-session (1.0.2)
@@ -283,7 +283,7 @@ DEPENDENCIES
   minitest (= 5.18.1)
   minitest-reporters (= 1.6.0)
   pgtk (= 0.8.1)
-  rack (= 2.2.6.4)
+  rack (= 2.2.8)
   rack-ssl (= 1.4.1)
   rack-test (= 2.1.0)
   rake (= 13.0.6)