The Password Manifesto Revisited
Password aging should be retired, usually . . .
There is never 100%, even in manifestos!
Another one of those Dan’s New Leaf Posts, meant to inspire thought about IT Governance . . . .
So several years back I became known as the auditor who had the audacity to propose that Password Aging was an aged control. If you don’t know what I mean by password aging, you could read that article. But know by the end of this article you’ll have a very good understanding of “aging as a control.”
Since that manifesto, audit Clients everywhere would rejoice as we suggested they tighten other password management controls and then consider lengthening their aging requirements.
That was then. This is now.
And I still stand by the entire philosophy. With a twist though.
The twist is really a reminder. I said “sometimes.” The twist is this: Password Aging can sometimes still be an effective control.
More importantly, let’s be teaching our users that password resets should be triggered, not periodic, and in some cases password aging is still an effective control.
Let me explain:
I still maintain that requiring people to change their passwords only increases the likelihood they’ll fight the system, write it down, or whatever. And now that we all know how to use very strong passwords, pass phrases, and random password generators, the need to change passwords to protect against CRACKING does not justify the cost.
When I heard about the Anthem breach, I did not need to change all my other passwords because I didn’t even remember my Anthem password. It was not a “theme password,” meaning that it did not have any core passwords (if you’re still not following me you really need to toss in the towel and read my original article.) I am very organized about my passwords so I knew that, from an authentication perspective, the Anthem breach did not compromise all my other passwords.
However, I did use, a few years back, a certain “core” for my “entertainment” passwords. Thus, when StubHub was breached, I had to change my password on Ticketmaster, whitesox.com, and the Todd Rundgren website. Since then I started using random passwords and thus the second time Ticketmaster was breached was only the second time I had to change the password there.
The point being is that the need to change your password is a “triggered need.” It should be caused by you remaining aware of the health of the systems you have placed confidential information, and if you think somebody has compromised your password, change it. If you hear that a system was compromised and the password you are using there, or any part of it, may have been compromised, change that password.
Is there still a good use for “password aging” . . . . periodic required password changes? Yes! My mother is a bit trusting of people, and has twice now fell pray to credit card pretext calling scams. So we now change her credit card number bi-annually. More instructive, we also change our own credit card at infotex once per year. The security benefits of this are still probably low, but the non-security benefits (that our contracts don’t auto-renew because our credit card has changed) is still worth the effort.
And to protect against bad threat intelligence (you not hearing about the breach of a system that has passwords you use in other systems), password aging is an effective control. So a balance needs to be stricken between the cost of changing your password every 42 days and the risk of not changing your password ever.
The point being is that there is never 100% in security. That’s why we work in layers of controls. If you’re using the same password everywhere, 42 days is probably too long now that the companies who ignored security are being hacked. But if you are using strong passwords, unique to each asset, and you are watching the breach news . . . . your aging can be as long as six months, in this auditors’ opinion.
The title of my manifesto is Sometimes Say Never. Yes, in general password aging is not an effective control. But in specific situations, it still makes sense.
And password aging makes a great illustration of how the strength of, and need for, any individual control depends greatly upon the entire control structure.
Original article by Dan Hadaway CRISC CISA CISM. Founder and Managing Partner, infotex
Dans New Leaf is a fun blog to inspire thought in the area of IT Governance.