diff --git a/2018/Slackbot/Gemfile.lock b/2018/Slackbot/Gemfile.lock
index f7d1e37..fc5db88 100644
--- a/2018/Slackbot/Gemfile.lock
+++ b/2018/Slackbot/Gemfile.lock
@@ -2,7 +2,7 @@ GEM
   remote: https://rubygems.org/
   specs:
     mustermann (1.0.2)
-    rack (2.0.4)
+    rack (2.2.3)
     rack-protection (2.0.1)
       rack
     sinatra (2.0.1)