diff --git a/Gemfile b/Gemfile
index d0f2a4f..276bcc4 100644
--- a/Gemfile
+++ b/Gemfile
@@ -2,7 +2,7 @@ source "https://rubygems.org"
 
 ruby "2.4.5"
 
-gem "rack", "~> 2.1", ">= 2.1.4"
+gem "rack", "~> 2.2"
 gem "yajl-ruby"
 gem "librato-metrics", "~> 1.3.0"
 gem "sinatra", "2.0.2"
diff --git a/Gemfile.lock b/Gemfile.lock
index 9e0f9cc..ad509c4 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -31,7 +31,7 @@ GEM
     public_suffix (4.0.6)
     puma (4.3.12)
       nio4r (~> 2.0)
-    rack (2.2.3)
+    rack (2.2.6.2)
     rack-protection (2.0.2)
       rack
     rack-ssl (1.4.1)
@@ -99,7 +99,7 @@ DEPENDENCIES
   librato-metrics (~> 1.3.0)
   pry
   puma (~> 4.3.12)
-  rack (~> 2.1, >= 2.1.4)
+  rack (~> 2.2)
   rack-ssl (>= 1.4.1)
   rack-test (>= 0.6.2)
   rack-timeout