diff --git a/core/dovecot/conf/dovecot.conf b/core/dovecot/conf/dovecot.conf
index 6c897710..e3c97ef5 100644
--- a/core/dovecot/conf/dovecot.conf
+++ b/core/dovecot/conf/dovecot.conf
@@ -57,6 +57,7 @@ namespace inbox {
 ###############
 auth_mechanisms = plain login
 disable_plaintext_auth = no
+ssl_protocols = !SSLv3
 
 passdb {
   driver = sql