This site gives great explanations and pictorial references to actual CUDS. Read through it to understand what a CUD is and how it is formed. Afterward you will see that the coin you have posted doesn´t resemble a CUD, but is just as posted by members, heat damaged. http://cuds-on-coins.com/
Well it's not a cud, as defined by many, but I'd say heat damage, like it's been in a hot fire, so it falls under Environmental Damage. Just my thoughts on it.
When did Franklin get put on the dime? Maybe Roosevelt got scared off by the fire and asked Franklin to take his place.