diff --git a/Gemfile b/Gemfile
index 46c1d9d4..b1d528d3 100644
--- a/Gemfile
+++ b/Gemfile
@@ -10,7 +10,7 @@ gem 'sinatra'
 gem 'thin'
 gem 'daru'
 
-gem "rack-test", "~> 2.0", :group => :testing
+gem "rack-test", "~> 2.1", :group => :testing
 
 gem "test-unit", "~> 3.5", :group => :testing
 
diff --git a/Gemfile.lock b/Gemfile.lock
index c5b8a9b8..5ee198cd 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -24,11 +24,11 @@ GEM
       backports
     power_assert (2.0.2)
     prometheus-client (4.0.0)
-    rack (2.2.4)
+    rack (2.2.6.4)
     rack-protection (2.2.2)
       rack
     rack-ssl-enforcer (0.2.9)
-    rack-test (2.0.2)
+    rack-test (2.1.0)
       rack (>= 1.3)
     redis (4.7.1)
     rexml (3.2.5)
@@ -57,7 +57,7 @@ DEPENDENCIES
   matrix (~> 0.4.2)
   prometheus-client
   rack-ssl-enforcer
-  rack-test (~> 2.0)
+  rack-test (~> 2.1)
   redis
   secure_headers
   sinatra