Edit Email Templates | System accepting CC Email address as invalid format and blank

Replication steps :

1)Open the Edit Template to End User url/Delinquent Email Template/Completed Forms Email Template.
2) Enter from email address
3) Add CC Email address with invalid format
4)System is allowing to save the template with "CC" email as invalid format and blank

Expected :
System should show proper validation message when "CC" email address is invalid format and blank