diff --git a/ruby/rails/webapp/Application/Gemfile.lock b/ruby/rails/webapp/Application/Gemfile.lock
index 6db7c143e..2b1f54ad6 100644
--- a/ruby/rails/webapp/Application/Gemfile.lock
+++ b/ruby/rails/webapp/Application/Gemfile.lock
@@ -90,7 +90,7 @@ GEM
       mini_portile2 (~> 2.3.0)
     public_suffix (3.0.2)
     puma (3.11.0)
-    rack (2.0.4)
+    rack (2.2.6.4)
     rack-test (0.8.2)
       rack (>= 1.0, < 3)
     rails (5.1.4)