diff --git a/6/Gemfile.lock b/6/Gemfile.lock
index 193fdbe..2f034b0 100644
--- a/6/Gemfile.lock
+++ b/6/Gemfile.lock
@@ -131,7 +131,7 @@ GEM
     popper_js (1.14.5)
     public_suffix (3.0.3)
     puma (3.12.1)
-    rack (2.0.7)
+    rack (2.2.6.2)
     rack-test (1.1.0)
       rack (>= 1.0, < 3)
     rails (5.1.7)