"While we only know of a few forum accounts that have been compromised, all forum users will be required to change their passwords the next time they login." I

"While we only know of a few forum accounts that have been compromised, all forum users will be required to change their passwords the next time they login." I am assuming here that this means certain passwords were cracked at that point - does this mean that the nonce/salt in their password storage was discovered? And how long until they have a cracked user/password file?