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Ed Password Format - Strength and Safety

This difference could be accomplished if there were a standard password hasher built into the browser. Even if the user entered the same password for every site, hashing the password with the user name and a site provided sequence code would insure that each site sees a unique passcode. Sites could even rotate the sequence code to increase security because each login would setup a new code for the next one.
If I understand you, your idea works like this:

On your end, your master password + your user name + a sequence code from the server = a cryptographic hash that's sent to the server.

The problem is that the server has to validate that hash, so it also needs your master password + your user name + the sequence code it generated, so that it can regenerate the hash and compare it to what was sent. That means that if you use the same master password for every site then every site will have to know your master password, and that's no good.

I think you need to work on that some more. Your idea might be a useful defense against some other type of attack, but I don't think it addresses the problem we're currently discussing.
 
No, you never send the master password to the server. You always use the same process even for the first time when you create the account. The server only knows what it gets back when it suplies a specific sequence code.

To accomplish code rotation, the server would send two sequence codes: the fiert code is one that the server already knows and the second is one that the server wants to learn for next time.

Ther is still a problem with codes being intercepted. But the code will expire after the next login and any use would be discovered when the real user tries to login.
 
What is the security community consensus on writing down passwords with an offset (a simple cipher switch on text or algorithmic operation on numeric characters)?

I feel like I have too many different systems requiring passwords not to use the process above. Either I use the same password for different systems, or write down many different passwords with a bit of a switch. It seems that for the electronic world at large, the writing down system is more secure than re-using passwords (which, it seems to me, is only as good as the weakest system you use passwords on). This is in contrast to someone getting physical access to a password that is, say, 25% wrong on a per-character basis.
 
Any system you use is going to be less secure than the ideal system of using random passwords for everything and remembering them in your head. The facf that you cannot reliably remember a large number of random passwords that get changed every 60 to 90 days doesn't alter the fact that the administration did everything they could to enhance security so any breach must be the fault of the idiot users that can't follow rules.

In your case, using strong passwords that are different for each account maximizes security against outsider attacks. But writing them down (even in simple encrypted form) will weaken that security for insider attackers that can access that list. Simple encryptions are easily broken when enough sample are available to detect the patterns and fall almost immediately if the plaintext for any sample is known.

Someone that can access your list (which you store in the bottom drawer of your desk) and knows just one of your passwords (by looking over your shoulder or when you logged in using their terminal or from your account on their server) will have easy access to all of your accounts.
 
Someone that can access your list (which you store in the bottom drawer of your desk) and knows just one of your passwords (by looking over your shoulder or when you logged in using their terminal or from your account on their server) will have easy access to all of your accounts.


Of course if we go down the paranoia lane, even remembering all your passwords isn't safe enough: Someone could torture you or inject you with a truth serum in order to hack your facebook account.
 
Of course if we go down the paranoia lane, even remembering all your passwords isn't safe enough: Someone could torture you or inject you with a truth serum in order to hack your facebook account.
More realistically, a judge could order you to reveal your password, and the only way you could keep out of trouble would be to prove that you don't even know the password yourself. This would be possible if the password was very long, random, and unmemorable, and you had it printed on a piece of paper that you destroyed before the judge gave you the order.

The only remaining challenge is to print the password in such a way that you need to know a secret to read it back correctly.
 
More realistically, a judge could order you to reveal your password, and the only way you could keep out of trouble would be to prove that you don't even know the password yourself. This would be possible if the password was very long, random, and unmemorable, and you had it printed on a piece of paper that you destroyed before the judge gave you the order.

The only remaining challenge is to print the password in such a way that you need to know a secret to read it back correctly.


That still leaves you in contempt for not revealing the secret. If you want to be safe from a judges order you need to place the secret itself outside the reach of the judges jurisdiction.

There are techniques to divide a secret into multiple parts where you need some subset of those parts to reconstruct the secret. This could be used to share the master secret with several friends in different countries. When you destroy your copy of the master password, you yourself cannot recover the passwords unless you convince enough of your distant friends that you are no longer under threat of legal prosecution.

eta: this could be problematic if one of the passwords was to your facebook account which is your only link to outside friends
 
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That still leaves you in contempt for not revealing the secret.
No, I don't think so. When would you have committed this supposed contempt? Was it when you destroyed the paper? Were you guilty of not foreseeing a future order that the judge hadn't even given you yet? Or did you commit contempt when you proved to the judge that what he asked of you do was impossible?

You can't reveal a secret if you don't know it.
 
Ah, I was misreading your plan. The printed secret requires a second secret to convert in into the real password so if the paper is lost it won't reveal the password.

But that leaves you vulnerable on the other side where the threat of legal action prompts you to burn the paper and forever loose access to the data you are protecting.
 
But that leaves you vulnerable on the other side where the threat of legal action prompts you to burn the paper and forever loose (lose) access to the data you are protecting.
You've already lost that whether you have the password or not, but this strategy could keep you out of trouble.
 
I don't get the assumptions of those brute force calculators.

How can a breaker possibly run 500,000 to 1MM checks a second? Sure, generate the passwords, but then actually connect to my PC (or the bank's server, or whatever) and attempt to crack. Don't they all have significant throttles to speed for this?

In any case, with my no special characters password, at 500K checks a second I'm told it would take 710758 years for 20,000 computers to crack my current password. Yet, I'm forced by site 1 to use a special symbol, another to use a capital letter, another NO special symbol, etc. Arbitrary rules that make it impossible to even generate a passphrase algorithm that applies to all cases. So, everything is written down. Great security. :rolleyes:

I mean, seriously, who is going to use 20,000 computers for 710758 years to crack my bank account? It's not like my last name is Gates or Buffett.
 
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You've already lost that whether you have the password or not, but this strategy could keep you out of trouble.


You are assuming a point after the court has already seized the hard drive and all backups. By such time, you yourself could already be in custody and incapable of carrying out the plan to burn the secret. Before it reaches that point, you could have decided that it was too hot and preemptively destroyed the master secret knowing that you would be able to recover it if things cooled down.

For a simple secret sharing plan, assume you create 3 random large numbers. One you keep for your self and the other two you securely deliver to two friends in different countries. The master secret is simply the sum of these 3 numbers. Now, even if there is an international judicial conspiracy and all three of you are ordered by the courts to reveal your copy of the secret, when the resulting sum doesn't unlock the data, who gets charged with contempt for producing the wrong number?
 
I don't get the assumptions of those brute force calculators.

How can a breaker possibly run 500,000 to 1MM checks a second? Sure, generate the passwords, but then actually connect to my PC (or the bank's server, or whatever) and attempt to crack. Don't they all have significant throttles to speed for this?

In any case, with my no special characters password, at 500K checks a second I'm told it would take 710758 years for 20,000 computers to crack my current password. Yet, I'm forced by site 1 to use a special symbol, another to use a capital letter, another NO special symbol, etc. Arbitrary rules that make it impossible to even generate a passphrase algorithm that applies to all cases. So, everything is written down. Great security. :rolleyes:

I mean, seriously, who is going to use 20,000 computers for 710758 years to crack my bank account? It's not like my last name is Gates or Buffett.

Now witness the fire power of this fully armed and operational distributed computer network. Seriously, there's an estimated half a million zombie PCs online.
Writing down your passwords is only as insecure as the place you keep them. The President of the USA has the nuke launch codes written down and carried by a guy who follows him around 24/7. For less sensitive data, a pocket-sized notebook will do.
 
Now witness the fire power of this fully armed and operational distributed computer network. Seriously, there's an estimated half a million zombie PCs online.
Well, that's my question. Does anyone chain together several million zombie PCs, all to attack one computer account, and, if so, is it effective given the measure put in place to shut down accounts with multiple bad password guesses? It's a serious question, does this really happen? With half a million PCs working nonstop, it'd take 3/4 of a million years to crack my "insecure" password.

My guess is that social engineering is the usual path: emails stating "oh noes! your account has been compromised, log onto our website with this handy link and enter your password now!!!!"

And, oh ya, the waiter stealing my credit card number when he runs my bill.

edit: it would also be my guess that the zombie pcs are attacking things like Amazon servers and the like, where there are several million CC# for the taking, rather than my bank account with a few digits worth of cash in it.
 
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No, you never send the master password to the server. You always use the same process even for the first time when you create the account. The server only knows what it gets back when it suplies a specific sequence code.

To accomplish code rotation, the server would send two sequence codes: the fiert code is one that the server already knows and the second is one that the server wants to learn for next time.

Ther is still a problem with codes being intercepted. But the code will expire after the next login and any use would be discovered when the real user tries to login.

You seem to be alluding towards a system similar to how Kerberos works.
 
Well, that's my question. Does anyone chain together several million zombie PCs, all to attack one computer account, and, if so, is it effective given the measure put in place to shut down accounts with multiple bad password guesses? It's a serious question, does this really happen? With half a million PCs working nonstop, it'd take 3/4 of a million years to crack my "insecure" password.

My guess is that social engineering is the usual path: emails stating "oh noes! your account has been compromised, log onto our website with this handy link and enter your password now!!!!"

And, oh ya, the waiter stealing my credit card number when he runs my bill.

edit: it would also be my guess that the zombie pcs are attacking things like Amazon servers and the like, where there are several million CC# for the taking, rather than my bank account with a few digits worth of cash in it.

No, no no. Usually, attempts to brute-force a password are not done directly on a service (say, for example, Amazon, or a credit card site). Those are protected with timeouts, logs, etc. And few try to directly attack an end-users computer via password compromise because the amount of traffic needed to do an over-the-'net brute forcing would be all too noticable to the ISPs handling the traffic, not to mention the fact that you never know when you're either hitting a computer that is indeed protected with strong passwords, or walking right into a honeypot.

No, the largest number of "hacks" are indeed social, just like you think, and they don't involve compromising a password on a computer at all. But when you exclude those, many of the rest of the attacks that occur concentrate on operating system vulnerabilities, not password compromises (that, BTW, is part of the reason why Windows is always bugging you to install updates; a good chunk of those are security fixes). Once in on a computer, then they rip off the password (actually, the password hash), and it's only after that when they try to break it using a distributed network.

So why break the password of a computer you've already broken into? Because there's a damn good chance that password is used elsewhere, that's why. Or uses information that can be used to narrow down a further compromise elsewhere. This is especially true if the computer is on a managed network (like an Active Directory) and the system uses a single-sign on for other resources; one password, multiple resources.

So anyway, instead of bouncing off of the security setup, malicious intruders simply use the username, enter the cracked password, and they're in. You never actually try to work on the "lock" i.e. the password right at the point a user enters it. You steal the "key", i.e. the stored, encrypted form of the password, then you crack it so you can use that newly cracked key at all the locks it's used at without being noticed.

That's one way to do it. But the point is that malicious intruders know better than to attack the system or computer directly. That sets off too many alarms. No, the key for them is to steal the password and crack it in a way that doesn't alert the systems the password allows access to that it's being worked on.
 
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So, if I am reading you correctly ElMondo, fears about password strength are overblown? I can see wanting to keep somebody from using words in the dictionary or sport team names ("Broncos" Yankees"), but beyond that I consider a 8 character passphrase generated password more than enough for my personal use, no matter how 'insecure' it is if half a million pc's tried to brute force it.
 
So, if I am reading you correctly ElMondo, fears about password strength are overblown? I can see wanting to keep somebody from using words in the dictionary or sport team names ("Broncos" Yankees"), but beyond that I consider a 8 character passphrase generated password more than enough for my personal use, no matter how 'insecure' it is if half a million pc's tried to brute force it.

Do you mean password "strength" as in "complexity"? Or as "length"? Or, are you asking if people are worrying too much about password security regardless of whether they're complex and long?

If the last, then no: Using good, strong passwords is something simple that an end user can do on their own end to ensure better IT security. The fact that hashes are normally stolen in other ways does not mean that fears regarding passphrase security are overblown; on the contrary, malicious intruders are forced to work around like that because they're prevented from simple brute forces and increasingly more secure passwords.

If my posts are coming off as stating that password security is unimportant in the face of the types of attacks that occur, please help me identify what components of my posts lead to that conclusion. I very seriously want to post further and correct that misapprehension; it's my own damn fault if I led you in the wrong direction. Strong passwords are like having good locks on your front door; they stay important even if burglers are entering through the windows.
 
Do you mean password "strength" as in "complexity"? Or as "length"? Or, are you asking if people are worrying too much about password security regardless of whether they're complex and long?
No, I'm just saying if my password was q3y7b9o6 (which it is not, obviously), is that unacceptably weak? The brute force calculators, noting that there are no capitals or non alphanumeric symbols, and assuming half a million PCs are trying to crack it, would say that is too weak.
 
That should be considered a strong password, actually. The fact that it lacks capitals and special characters matters less than the fact that it is not subject to dictionary attacks.
 

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