diff --git a/config/filter.d/sendmail-auth.conf b/config/filter.d/sendmail-auth.conf
index a370eea2..752621f7 100644
--- a/config/filter.d/sendmail-auth.conf
+++ b/config/filter.d/sendmail-auth.conf
@@ -9,7 +9,8 @@ before = common.conf
 
 _daemon = (?:sendmail|sm-(?:mta|acceptingconnections))
 
-failregex = ^%(__prefix_line)s\w{14}: (\S+ )?\[(?:IPv6:<IP6>|<IP4>)\]( \(may be forged\))?: possible SMTP attack: command=AUTH, count=\d+$
+# "w{14,20}" will give support for IDs from 14 up to 20 characters long
+failregex = ^%(__prefix_line)s\w{14,20}: (\S+ )?\[(?:IPv6:<IP6>|<IP4>)\]( \(may be forged\))?: possible SMTP attack: command=AUTH, count=\d+$
 
 ignoreregex =