diff --git a/Gemfile.lock b/Gemfile.lock
index a60bd6a8c..02cb01652 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -160,7 +160,7 @@ GEM
     mini_mime (1.1.5)
     mini_portile2 (2.8.4)
     minitest (5.20.0)
-    net-imap (0.3.7)
+    net-imap (0.4.2)
       date
       net-protocol
     net-pop (0.1.2)