diff --git a/Gemfile.lock b/Gemfile.lock
index 01c8b571..da0743ba 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -135,7 +135,7 @@ GEM
       prism (~> 1.5)
     mustermann (3.0.4)
       ruby2_keywords (~> 0.0.1)
-    net-imap (0.6.3)
+    net-imap (0.6.4)
       date
       net-protocol
     net-pop (0.1.2)