diff --git a/images/webapp/app/Gemfile.lock b/images/webapp/app/Gemfile.lock
index 76abf9b..6ccede1 100644
--- a/images/webapp/app/Gemfile.lock
+++ b/images/webapp/app/Gemfile.lock
@@ -5,7 +5,7 @@ GEM
     eventmachine (1.2.7)
     hiredis (0.6.3)
     mustermann (1.0.3)
-    rack (2.2.3)
+    rack (2.2.6.3)
     rack-protection (2.0.7)
       rack
     redis (4.1.3)