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Comment: Re:Long View (Score 1) 466

by Tom (#49491483) Attached to: Seattle CEO Cuts $1 Million Salary To $70K, Raises Employee Salaries

Compensation has been commensurate to your skills for hundreds of years.

Your argument smells.

Yes, more skilled people in general earn more. But (and in the words of Ben Goldacre: It's a big but) there are exactly two issues with this in our modern hypercapitalism, and they are related:

a) A class of very low skilled workers has moved to the top of the food chain and takes a massive part of the total wages for itself

b) The general level of pay is staggeringly low. If you compare the wealth of your western nations to the wealth of the average individuals within, you should be frightened. Most western countries can spend a few billions here and there without so much as shrugging. As nations, we have more, much much much more money available than ever in history. The most lavish spending of any king in history pales compared to everyday infrastructure, science or military projects of today. As people, we are richer than the average middle ages peasant, but in comparison to our nations wealth, we have less.

Comment: Re: For work I use really bad passwords (Score 1) 136

by Tom (#49481065) Attached to: Cracking Passwords With Statistics

Then another site I used got hacked. And at that point I decided I was better off using a password manager and using different passwords for each site.

Yeah, that sucks.

I use a password manager as well, mostly because I'm lazy typing. It gives me the added benefit that if one of the sites gets hacked, I can check the PW manager to see where else I use the same PW.

You can use different passwords, if you like. I don't do it because it would mean that when I find myself without my PW manager, I'd be fucked. And it happens quite often that I do.

Comment: Re: For work I use really bad passwords (Score 1) 136

by Tom (#49481055) Attached to: Cracking Passwords With Statistics

The problem there is that all it takes is one crap site and an attacker can check all of your "reset answers" (pet's name / mom's name / etc) to see if they can be used for an attack.

These bullshit "security questions" are actually the weakest link. I don't use them. If the site enforces it, I fill them with noise.

Think about what the minimum information an attacker would need to access your bank account (either login or social engineering) and then look at how many sites have that information.

Depends on your bank. Mine doesn't let me log in with username or password or any such crap. Also, every bank worth its money these days will use 2-factor authentication, or send a TAN by SMS or something like that. More and more banks will also send you SMS to inform you about every transaction made, so you can stop any abuse immediately.

Banks are among the few who actually take security seriously. They're not perfect, not by far, but they are still among the only commercial entities to use one-time-passwords (those TAN lists) and were among the very first to use 2-factor authentication.

So, to answer your question: What do you need to access my bank account? Nothing you would find on any of the forums, games sites or even my Amazon or iTunes account.

Comment: Re: For work I use really bad passwords (Score 1) 136

by Tom (#49481025) Attached to: Cracking Passwords With Statistics

Changing passwords doesn't make them magically more secure.

What do you hope to accomplish? If you have a good reason to change, change. If you don't, you change for prophylaxis, to stop someone who may have been using your account for something. But if you didn't even notice, what's the damage? And if he's a pro, he's also changed the password reset email address, at least on sites that don't send a notice to the old address.

You're doing a lot of effort for - what? If you can't answer that question, don't do it.

Comment: Re:math (Score 1) 136

by Tom (#49480945) Attached to: Cracking Passwords With Statistics

No, it wouldn't help.

The problem is techies thinking in techie terms. What would help is get a normal user into the room and give him an actual voice in the matter, when the policy is decided. You know, not John from the call center, but Frank the philosophy doctor who's now head of product management.

Comment: Re:The assumption is wrong. (Score 3, Informative) 136

by Tom (#49476351) Attached to: Cracking Passwords With Statistics

The point of password complexity requirements has nothing to do with security. It's about the check box some auditor or lawyer needs to check. People assume it leads to security, but only because they see it in a vacuum.

That's consultant bullshit. The legal requirements are nowhere near this specific. It's only consultants that turn them into this nightmare of nonsense. I've worked in IT Compliance (SOX) for years. As long as you can describe why your password policy is good, it doesn't matter what it actually is. The problem is too many people don't invest the time to think a bit and simply take a so-called "best practice" and apply it. In way too many cases without reading to the end and realizing that this "best practice" was published in 1998 and may be a little outdated.

Comment: Re:subjects are stupid (Score 1) 136

by Tom (#49476345) Attached to: Cracking Passwords With Statistics

Still waiting for an article (actually, the posts so far also seem devoid) about pass-acronyms. "mhallifwwas" will pwn any brute force, any attack table (well, not any more) and it's a fscking nursery rhyme.

You can wait a long time, because there are too few computer scientists on the intersection of poetry, linguistic analysis and computer security to make that happen. You would need a good estimate of likely sentences used for input and that requires skills far outside the computing sphere.

A statistical analysis will likely reduce the set of probably letter combinations somewhat, but probably not by more than one or two orders of magnitude. An analysis of word-beginning distribution of letters will gain you more. Taking all that into account, my best gut feeling is that you'll end up somewhere in the area of 10^10 in complexity for an 8-character output. Better than passwords (which I've repeatedly estimated at around 10^7) but still not so great and probably much less than you'd expect.

Also, taking into account psychology and the fact that a fairly small set of phrases is much more popular than all the others combined, and that many users will choose a popular phrase instead of a personal one, you would also end up with the "password"-as-my-password problem in that a lot of accounts would have phrases from a list of maybe 1000 popular ones.

Comment: math (Score 5, Insightful) 136

by Tom (#49476327) Attached to: Cracking Passwords With Statistics

Been there, done the math, and I can confirm that the guy is 100% spot on. According to the slides of my last keynote on the subject, it basically goes like this:

We think the complexity of a password made in accordance to a typical password policy (at least 8 letters, at least 2 of them special characters or numbers, mixed upper and lower case) is on the order of 10^16.

What users actually read is more along the lines of "take a word, maybe abbreviate it, add one number and one of the easy-to-type special characters", giving us a complexity in the order of 10^7.

That's not a small difference. That's 9 orders of magnitude. That's like thinking the population of the USA is around 3000 people. That's how far off we are when we think about complexity of passwords in purely cryptoanalysis terms, without taking user preferences into account.

What this guy did is really great, I wish I had time to do such a proof-of-concept instead of just speaking about it every time I get an opportunity.

Comment: Re: For work I use really bad passwords (Score 5, Interesting) 136

by Tom (#49476309) Attached to: Cracking Passwords With Statistics

Your first comment is close. Yes, a serious attacker has many better ways than cracking your password. In fact, I've given another speech on this a few months ago where I basically said that we should drop brute-force as a threat scenario from our password strength estimations, because any software that even allows a brute-force attack to be run is fundamentally broken and needs to be discarded.

Same for cracking hashes, btw. If your software does not properly salt and hash, it's broken. It's 2015, not 1995.

Your second comment is totally wrong and one of the reasons we have so many bad passwords. We tell normal human beings to use a different password for each of the 200 or so sites that they have an account on, many of which they use once a year. That's idiotic, and users are telling us we're insane by ignoring it.

I use 3 different passwords for 90% of the accounts I have. One for all the various forums, social sites and other crap that is of absolutely no importance to me and if it gets leaked and you use it to log in as me on one of them, you can post comments in my name - omg, the sky is falling. One is for sites that I have some stakes in, like accounts in online games and such, where you could do some damage in the sense of destroying something that took me time to create (delete my GW2 characters, I'd hate you for it, but no real damage has been done). And one I use for sites where you could do some damage that I could probably reverse, but it would take effort and might cause me real-world inconveniences, such as shopping sites where you could order something in my name and I'd have to go and cancel the order or send it back or whatever.
My PayPal and banking accounts have their own passwords, as do my user accounts, database accounts and such. But for 90% or so of accounts, you don't really need a seperate password (and using password managers ties you to them, which is why many people don't do it).

And I'm a security expert giving speeches at conferences about these topics. I'm just not a blind one-trick-pony who knows all about cryptography and nothing about anything else. If you begin to figure in psychology, HCI and other topics as diverse as design and linguistics, a lot of what's wrong with IT security begins to emerge more clearly.

Comment: Re:Still cheating (Score 2) 114

by Tom (#49452013) Attached to: German Teenager Gets Job Offer By Trying To Use FOI For His Exam Papers

Which AFAIK they also can't do.

He found a valid loophole in the law, the combination of different unrelated government actions. Firstly they created a transparency law (good!) which applies to certain government institutions. Also, they centralized the exams - when I wrote my Abitur many years ago, questions were made locally, by the school you took it, mostly by the teacher who had given the course, so it was based on the material that had actually been taught. There are advantages and disadvantages to that. For whatever reasons, some time between my Abitur and now they centralized everything, which brought the exam questions into one of the government institutions covered by the transparency law. Whoops.

Always try to do things in chronological order; it's less confusing that way.