diff --git a/Gemfile.lock b/Gemfile.lock
index 9619ed6..222153d 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -13,11 +13,11 @@ GEM
       rexml
     diff-lcs (1.5.0)
     hashdiff (1.0.1)
-    mustermann (2.0.2)
+    mustermann (3.0.0)
       ruby2_keywords (~> 0.0.1)
     public_suffix (5.0.0)
     rack (2.2.4)
-    rack-protection (2.2.2)
+    rack-protection (3.0.4)
       rack
     rake (13.0.6)
     rexml (3.2.5)
@@ -35,10 +35,10 @@ GEM
       rspec-support (~> 3.11.0)
     rspec-support (3.11.1)
     ruby2_keywords (0.0.5)
-    sinatra (2.2.2)
-      mustermann (~> 2.0)
-      rack (~> 2.2)
-      rack-protection (= 2.2.2)
+    sinatra (3.0.4)
+      mustermann (~> 3.0)
+      rack (~> 2.2, >= 2.2.4)
+      rack-protection (= 3.0.4)
       tilt (~> 2.0)
     tilt (2.0.11)
     webmock (3.18.1)