diff --git a/Gemfile.lock b/Gemfile.lock
index 0474177..a66a650 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -163,7 +163,7 @@ GEM
       net-protocol
     net-protocol (0.2.1)
       timeout
-    net-smtp (0.3.3)
+    net-smtp (0.4.0)
       net-protocol
     nio4r (2.5.9)
     nokogiri (1.15.4)