diff --git a/Gemfile b/Gemfile
index 7c12cc71a..063b392f3 100644
--- a/Gemfile
+++ b/Gemfile
@@ -27,7 +27,7 @@ gem 'oh_delegator'
 gem 'open4'
 gem 'paperclip', '~> 5.3'
 gem 'pg', '0.20'
-gem 'rack', '~> 2.2.3.1'
+gem 'rack', '~> 2.2.6.3'
 gem 'rails', '~> 5.2.8'
 gem 'rails-html-sanitizer', '~> 1.4.3'
 gem 'ransack', github: 'activerecord-hackery/ransack'
diff --git a/Gemfile.lock b/Gemfile.lock
index 49a9de325..51a9bf333 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -315,7 +315,7 @@ GEM
     pg (0.20.0)
     public_suffix (4.0.6)
     racc (1.6.1)
-    rack (2.2.3.1)
+    rack (2.2.6.3)
     rack-test (2.0.2)
       rack (>= 1.3)
     rails (5.2.8.1)
@@ -527,7 +527,7 @@ DEPENDENCIES
   open4
   paperclip (~> 5.3)
   pg (= 0.20)
-  rack (~> 2.2.3.1)
+  rack (~> 2.2.6.3)
   rails (~> 5.2.8)
   rails-controller-testing
   rails-html-sanitizer (~> 1.4.3)