The comments on this blog post make me cringe. Is there a correlation between Schneier followers and self-professed experts? Consider the clever fellow who has "logically" concluded that consistent password rules would constitute "putting all your eggs in one basket" and hence weaken security. Folks: a limited character set isn't a liability if you can just increase the number of characters correspondingly. If you're allowed a 64 character password, you can reduce the character set to [0-9A-F] and still have 2^256 possibilities.
I hate password rules
421–430 of 447 posts
Re: I hate password rules
#422Earlier quoted context omitted.
If you require as few as 9 characters, without requiring special characters, the security is poor. The reason is that users do not choose random strings of letters, so the entropy per character is low. If we assume an entropy of 2 bits per characters (which is generous if the user uses dictionary words), then 9 characters gives us 18 bits. A 9 character password could easily be as poor as a random 18 bit integer. If…
So "fishyidea" has less or equal entropy to "262119"?
Neither fishyidea nor 262119 show up in haveibeenpwned's database, so they're at least uncommon. Neither of them look to have much entropy, though.
2x211y doesn't look very random to me. 2 and 1 are consecutive, and there are only 4 distinct digits here. Even if it was randomly generated, a good password generator would probably discard it for being akin to passwords that humans tend to generate. (This is especially true when you impose minimum lengths to passwords. "26219 isn't long enough? Fine. 262119.")
Fish and idea are both among the top few thousand most common words. Searching adjective+noun pairs is going to be much more fruitful than searching arbitrary word pairs, and ideas can in fact be fishy, so it makes sense to guess that particular adjective+noun pair before trying metamorphicidea.
Re: I hate password rules
#423My frustration isn't just the sites that make the password rules clear after I submit the form. The worst sites are the ones that truncate my generated password to fit their maximum password length and then don't tell me (which seems to happen in more places than it should).
My favorite one was a site that capped the password length in the creation form in a way you couldn't tell it was being truncated, but then let you enter any length when you logged in. And being a finance thing, it blocked your password after three attempts.
Re: I hate password rules
#424A few years back, not too long ago, I started working on a new contract assignment at a medium size aerospace manufacturer. I show up and check in with IT department. The system administrator shows me to my desk, and hands me a post it note with my password. Well pass phrase is more like it. It was something like “sliding down the tall building”. I was quite impressed that they encouraged the use of long pass phrases…
The funnier thing about that story is that the passphrase they gave you is not necessarily secure in the first place if we're talking about a scenario where a hash is found. While length is a factor when brute forcing randomness, any words or phrases that commonly appear together in written text are likely to come up in various types of dictionaries that can be used in more sophisticated brute forcing algorithms. "sl…
The nice thing with the lists of multiple randomized words is that there are so many more combinations possible. The numbers, which will be individual digits for most people, add relatively little here.
Using EFF's dice-ware page (https://www.eff.org/dice) as an example, the long word-list has 7776 entries, with a nicely random way to select them. Four of those words is already a sixteen-digit number in the combinations available. Even their short list of 1296 words would provide pretty reasonable odds. The key is to use something like the dice that takes away our own biases when selecting words.
Re: I hate password rules
#425More than once have I used the password rules to reverse engineer a lost password.
I think it’s just better if their system provides a little complexity indicator.
Re: I hate password rules
#426Earlier quoted context omitted.
If you require as few as 9 characters, without requiring special characters, the security is poor. The reason is that users do not choose random strings of letters, so the entropy per character is low. If we assume an entropy of 2 bits per characters (which is generous if the user uses dictionary words), then 9 characters gives us 18 bits. A 9 character password could easily be as poor as a random 18 bit integer. If…
So "fishyidea" has less or equal entropy to "262119"?
I would say it has better entropy, but not by much.
The word "idea" appears list of 850 common words:
https://en.wiktionary.org/wiki/Appendix:Basic_English_word_l...
"fish" is ranked #1453 in the list of lemmas linked from here:
https://en.wiktionary.org/wiki/Wiktionary:Frequency_lists#To...
We can arithmetically encode the choice of two words from dictionaries of 1000 and 1500, respectively, using 21 bits.
The two bits estimate is a somewhat pessimistic lower bound.
Re: I hate password rules
#427Earlier quoted context omitted.
To verify, you're using a password manager? Because it's hard to imagine someone getting upset over having to just update an entry, and obviously the bank can't tell you not to use a password to unlock your own vault. And I can't imagine someone memorizing a password for a bank login only, and never using that in other locations. The internet requires so many accounts to manage... If you did reuse your password then…
I use securely generated passwords based on a cryptographic hash. I don't use a "password manager". Someday 10^8 people who use a password manager are going to get their passwords stolen in one night and I'm not going to be one of them.
Most password manager ecosystems consider this vector. They're either zero knowledge (bitwarden, lastpass ...), local(keypass, pass, buttercup ...), or are vulnerable in the way you describe and suck.
Hashing is sure an interesting way to create passwords. I've considered it as well. I liked that it protects you from credential stuffing and it's stateless. But I found it hit practical roadblocks I couldn't route around:
* you need a plaintext that wont change at the site, but will change across sites. URL is most common, but URL's can change.
* if that site does have password requirements and your digest fails to meet those requirements, you have to either iterate or alter your plaintext (and remember) or alter your digest (changes everything), or alter for that specific site (and remember).
* sites often have password rotation requirements because users frequently use bad passwords across sites and that basically forces you to remember state.
* If you store any of this state, it's no longer stateless and you hit all the problems of syncing across devices and so on and so forth.
What do you use for your plaintext anyway?
Re: I hate password rules
#428Earlier quoted context omitted.
My work is also big on pass phrases but I kinda hate them. It's a lot of extra work to type it every time I unlock my PC. And more characters means there's more chance to make a typo meaning I have to do the whole thing again. And the weird way my brain works I have no issue remembering "G6bH,vIz#amV" so I still do it like that :) Also, if an attacker has a hash of my password the damage is already done anyway. They…
What's stopping you from using a random password like 'G6bH,vIz#amV'?
Well they wanted to set the minimum length at 16 characters, for one :)
But in the end they settled on 10 so it's ok. They even made it mandatory to have special chars and numbers if you have less than 16. So in the end it worked out fine for me but it did take some convincing (I was involved with the team that was making the choices).
Tbh even if you do have to brute-force, if you know the company is using passphrases, it tends to be similar in terms of difficulty as a complex shorter password to brute force it. Because you can do a combined dictionary attack. And it's more susceptible to targeted attacks e.g. gathering a person's interests on facebook.
Re: I hate password rules
#429Earlier quoted context omitted.
My work is also big on pass phrases but I kinda hate them. It's a lot of extra work to type it every time I unlock my PC. And more characters means there's more chance to make a typo meaning I have to do the whole thing again. And the weird way my brain works I have no issue remembering "G6bH,vIz#amV" so I still do it like that :) Also, if an attacker has a hash of my password the damage is already done anyway. They…
> They can do a pass-the-hash attack, they don't even need to brute force it for the plaintext. Ok, but that's a very Windows-specific issue. I don't know of any other widely-deployed system vulnerable to pass-the-hash.
That's true but we're a Windows shop, sadly :)
I'm a bit appalled at the security of AD with PTH, Kerberoast etc. In some cases you can even continue to use a nabbed ticket after the compromised account has been locked! That should never be possible IMO.
I'd love to move on from AD personally. But you know... Legacy galore.
Re: I hate password rules
#430A few years back, not too long ago, I started working on a new contract assignment at a medium size aerospace manufacturer. I show up and check in with IT department. The system administrator shows me to my desk, and hands me a post it note with my password. Well pass phrase is more like it. It was something like “sliding down the tall building”. I was quite impressed that they encouraged the use of long pass phrases…
The funnier thing about that story is that the passphrase they gave you is not necessarily secure in the first place if we're talking about a scenario where a hash is found. While length is a factor when brute forcing randomness, any words or phrases that commonly appear together in written text are likely to come up in various types of dictionaries that can be used in more sophisticated brute forcing algorithms. "sl…
Really the key is using words that aren't in a dictionary, or at least not the same dictionary. It's pretty trivial for a brute force attack to just take a list of English words and try them in a large number of combinations. But if you have some non-english words, as far as that attacker is concerned its random gibberish. Of course the attacker might use a few languages so just mixing say english and spanish won't do that much better, but if you got some navajo or some quenya you're likely immune to any attack that isn't specifically targeted at you. And it doesn't even have to be a foreign language, even many proper nouns won't show up in a dictionary. For a password like "PoggleExclaimsGeonosianBarahunde" or "Seanbeanfearsburzum-ishikrimpatul" it would take trillions of years to guess a password without very specific pop culture knowledge.