Slashdot Mirror
Password Memorability and Securability
NonNullSet writes "Who would have thought that that something new could be said about how best to select passwords? Ross Andreson of Cambridge University and some of his colleages have performed new empirical studies and found some pretty non-intuitive results. For example:
1. The first folk belief is that users have difficulty remembering random passwords. This belief is confirmed.
2. The second folk belief is that passwords based on mnemonic prases are harder for an attacker to guess than naively selected passwords. This belief is confirmed.
3. The third folk belief is that random passwords are better than those based on mnemonic phrases. However, each appeared to be just as strong as the
other. So this belief is debunked.
4. The fourth folk belief is that passwords based on mnemonic phrases are harder to remember than naively selected passwords. However, each ap-
peared to be just as easy to remember as the other. So this belief is debunked.
5. The fifth folk belief is that by educating users to use random passwords or mnemonic passwords, we can gain a significant improvement in security. However, both random passwords and mnemonic passwords suffered from a
non-compliance rate of about 10% (including both too-short passwords and passwords not chosen according to the instructions). While this is better than the 35% or so of users who choose bad passwords with only cursory instruction, it is not really a huge improvement. The attacker may have to work three times harder, but in the absence of password policy enforcement mechanisms there seems no way to make the attacker work a thousand times
harder. In fact, our experimental group may be about the most compliant a systems administrator can expect to get. So this belief appears to be debunked."
Freaking PDF files. Link to a version translated into HTML. By the time this goes live, maybe the FTP will be slashdotted, too. Thanks, Google.
I suppose I should make a comment. Okay, here it is: looks like users are still the weakest link in security. Whoever said that social engineering was the ultimate hack is a genius.
Google's HTML Cache Version
Hmmm.
Mitnick had a neat suggestion in the Art of Deception. The Consonant-Vowel Method. It provides an easy to remember password because it is pronounceable. You take the following template and swap in consonants and vowels: CVCVCVCV. The examples he gave are MIXOCASO and CUSOJENA. The point is they won't be in the dictionary but you can remember these nonsense words.
Support the First Amendment. Read at -1
Yeah, passwords and standards are fine as long as you keep snickers out of the office
One area I'd like to see would be strength of a password in terms of randomness, requireing use of characters, etc. vs length. Is an 8 character password with a punctuation mark better than a 10 character pasword with all lower case characters? If so, by how much?
Then we can determine a good password policy that fits with the security model at the facility.
How many passwords have you got? turn on pc, open email, encrypted files, bank account login's, ftp login's, forum memberships, the list goes on. How many have you forgotten? We need a better authentication system than text passwords. Security agencies have developed stunning biometrc identification technologies, perhaps these could be put out for the general public to use?
Do you need a website upgrade?
Hah! Now I also know how to reach you on the phone...
This comment does not exist.
"Hello, I'm doing a study for the Cambridge University Computer Laboratory on passwords..."
If IT keeps warning, they're told to stop worrying. If something happens, IT is blamed. These morons (leaders) need to figure out that IT isn't something that helps them do business. Their business runs on IT. Without it, they have no business.
Hoist Number One and Number Six.
Most of the time, people just don't care. And why should they?
I probably have 200 passwords floating around in cyberspace, and 90% of them are "password". For example, I have to supply uid/pwd in order to read the Washington Post (my local newspaper). Is it important to keep this password secret? No, because I'm not very worried about someone reading the newspaper under my name.
Unless I have confidential personal information at stake, I am not usually motivated to create a strong password.
So, sysadmins, if the security of your overall network is more important than Joe User's individual data, you need to enforce strong password rules. Relying on users to create strong passwords voluntarily under such conditions is foolish.
The most rabid believers in American Exceptionalism are the exact same people whose policies are destroying it.
Perhaps I'm crazy but I've always felt an application which allows a brute force attack is flawed.
Surely by this point in software development it should be regarded as standard for every program to LOCK access for a given account after X consecutive failed logon attempts?
Even setting this to something arbitrarily high like, say 1000, is more than any user would ever try before asking for help, but much MUCH MUCH less than any dictionary attack would require. Combine this with the possibility of real time notification for admins (facilitated by email/inter application messaging, or a small add-on service for the OS) when more than Y accounts are locked for this reason in Z minutes, and as a community we'd effectively end all dictionary attacks - or at least turn them into DOS attacks, but at least we'd know it was going on...
Stay late one night. After they are all gone walk from desktop to desktop. Look for post-it notes on the side of the monitor and under the keyboard, and in their drawers. The results will scare you, if your users are anything like mine, and I bet after that you start letting them pick less cryptic passwords.
Also, if you know their password there goes any semblance of Non-Repudiation. And if you can 'remind them' either you have a very short list of users and can remember them, or you have a written list somewhere - nifty, but a bad idea.
Glonoinha the MebiByte Slayer
My menmonic, which should have been hard for people to guess, was "Please ask sister sally where's our rottweiler dog"
And the thing is, we didn't even have a rottweiler, it was a shepherd. But people still guessed it, so I don't use mnemonics anymore.
Do not taunt Happy Fun Ball(TM)
Using the term "folk belief" more than once in a paragraph can become very annoying. This belief is confirmed.
----------------------------------
I'd rather not take sides until I hear the monkey's version - PHB
Or use SHA2. Cause I don't have rainbow tables to crack that. Yet. For those of you who don't or cannot follow security, the new buzz is creating your own crack tables in a couple of weeks or months. There is more info at the project rainbowcrack page.
The misconception that everyone has about passwords now (because we as sysadmins pushed it so hard in the late 90s, early 00s) is that alphanumeric is the way to go. With the advent of generating your own cracking tables, that is no longer the case anymore.
An alphanumeric md5 set of rainbow tables can be generated in about a weeks time with a 2.4 ghz processor. That's my rough estimate based on the couple days it took me to make the alphanumeric one for LM hashes.
I would highly suggest that if you want your users to come up with good passwords you have them make a "one-time" password, seed with a 20-character salt that looks like someone pounded the keyboard, and store it inside a SHA2 hash.
A good administrator is going to salt their passwords with a string of characters that already satisfies the "alpha-numeric-symbol" requirement. If there is any reason to do something other than the first name of your child it is to stop coworkers or friends or people that already know about you.
When using brute-force/guess method this is what I try first and my guess is that at least 1% of Slashdot fathers use this or a form of it as their pass. It's okay to be proud of your kid, but don't think you're honoring them by including them in your password.
Well when going through a really rough divorce (I had an easy one too) I was in serious fear , and justifably so of my Ex hacking accounts using some of my known Passwords , I like many others have a cycle of about 10 that are used interchangably. All these were , with the exception of 1 personal passwords. I found she was accessing my work mail and personal mail almost immediatley , Soooo I decided to have some fun with it, passing all kinds of bogus information into forged emails to myself. Then came court, she was ACTUALLY Stupid enough to bring up several points in court, my Attorney was aware and asked where she found this informationout, "Around, friends, etc" Bwwwahhaaaa talk about someone looking stupid she bought it hook line and sinker.
:)
Sometimes easy to crack passwords are a GOOD thing
On another note, after I took her to the cleaners at court I decided to TIE one One, well....NEVER....and I mean NEVER....change you passwords while really drunk..it took me 2 days to reconfigure redit and reset all my passowrds I changed on that drunken celebration. I still have NO idea what some of them were or how I came to decide on their usage
-The Libra
"You've got no kids, no wife, no job, and you're not in The Tigger Movie!!!"
- my best friend's son, Gabe, at 5 years old.
-The Libra
"Please be patient--The future will begin momentarily."
I occasionally like memnonic passwords, but another good alternative is a randomly-generated but pronounceable password. It turns out that we're much better at remembering passwords that we can pronounce. (Where "Voolakun5" is pronounceable and "zqx17yvy" is not).
FIPS-181 describes a NIST-endorsed system for producing pronounceable passwords. There is a GPLed FIPS-181 implementation here.
Sample run:
$ apg
dyijenuloa
bifliecar
yishjied&
IfHydrovia
yutsOlg/
DipUkcat
APG is a lot more sophisticated than this, and allows you to do a lot of tweaking of the types of passwords it outputs, print pronunciation guides. It's a good tool, IMHO, for security-conscious types to have around.
For Fedora Core 2 users, Red Hat does not package apg in the base distribution, but it is available from freshrpms.
May we never see th