diff --git a/apps/epp_proxy/priv/test_backend_app/Gemfile.lock b/apps/epp_proxy/priv/test_backend_app/Gemfile.lock
index 9a31267..ebfb1a5 100644
--- a/apps/epp_proxy/priv/test_backend_app/Gemfile.lock
+++ b/apps/epp_proxy/priv/test_backend_app/Gemfile.lock
@@ -4,7 +4,7 @@ GEM
     nio4r (2.7.4)
     puma (6.6.0)
       nio4r (~> 2.0)
-    rack (3.1.16)
+    rack (3.1.21)
     rack-unreloader (2.1.0)
     rackup (2.2.1)
       rack (>= 3)