Passwords of sufficient complexity mitigate the threat of brute-force attacks without having to be changed. And, if you know a user's password this month, you are probably 95% of the way to knowing his password next month (change a digit at the end, pick the next kid's name, etc.).
-Malcolm From: John Hornbuckle [mailto:john.hornbuc...@taylor.k12.fl.us] Sent: Friday, April 16, 2010 07:52 To: NT System Admin Issues Subject: RE: please don't change your password! There's a flaw in the logic. The Globe article states: " . . . [U]sers are admonished to change passwords regularly, but redoing them is not an effective preventive step against online infiltration unless the cyber attacker (or evil colleague) who steals your sign-in sequence waits to employ it until after you've switched to a new one, Herley wrote. That's about as likely as a crook lifting a house key and then waiting until the lock is changed before sticking it in the door." This fails to consider the situation where a user's password is compromised and the bad guy accesses the user's information on an ongoing basis. For instance, monitoring a folder that contains files with information about patent filings to see when new files show up, or logging into OWA to keep an eye on e-mail messages. The unauthorized access will end once the password is changed (assuming a variety of other factors, such as the bad guy not getting the new password, etc.), and thus requiring regular password changes can be of value. Similarly, regular password changes can mitigate the risk from brute-force attacks. If a password has to be changed every 60 days, for instance, the bad guy will only have 60 days to try to determine the user's password. This is generally considered to be better than the bad guy having an infinite amount of time to try to determine it. John Hornbuckle MIS Department Taylor County School District www.taylor.k12.fl.us From: Brian Clark [mailto:brianclark2...@googlemail.com] Sent: Thursday, April 15, 2010 4:38 PM To: NT System Admin Issues Subject: please don't change your password! After a long week doing a SBS migration I didn't know how to take this article and needed to share it!! http://www.boston.com/bostonglobe/ideas/articles/2010/04/11/please_do_not_ch ange_your_password/?page=1 Brian NOTICE: Florida has a broad public records law. Most written communications to or from this entity are public records that will be disclosed to the public and the media upon request. E-mail communications may be subject to public disclosure. ~ Finally, powerful endpoint security that ISN'T a resource hog! ~ ~ <http://www.sunbeltsoftware.com/Business/VIPRE-Enterprise/> ~