diff --git a/lib/msf/core/exploit/remote/smtp_deliver.rb b/lib/msf/core/exploit/remote/smtp_deliver.rb
index c0a136e3ee..52836e0d48 100755
--- a/lib/msf/core/exploit/remote/smtp_deliver.rb
+++ b/lib/msf/core/exploit/remote/smtp_deliver.rb
@@ -244,6 +244,10 @@ module Exploit::Remote::SMTPDeliver
     begin
       nsock.put(cmd)
       res = nsock.get_once
+      # read until `nil` is returned
+      while chunk = nsock.get_once
+        res += chunk
+      end
     rescue
       return nil
     end