Specific to the security of passwords: hashing, entropy, cracking, resets, lockouts, etc.

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5
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4answers
291 views

Should we be checking password restraints on log in forms?

We have many restraints we put on users when they set up their password. These restraints include password length, characters they can or cannot use, the use of numbers and letters, capitalization ...
29
votes
4answers
5k views

What should be used as a salt?

I always hear that it is best to use salts on top of stored passwords, which then somehow gets concatenated and hashed afterwards. But I don't know what to use as a the salt. What would be a good ...
17
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2answers
2k views

Essential things to think about before outsourcing authentication with OpenID, OAuth, or SAML

It's clear there there is no consistent set of features among any of the popular authentication providers. Below is an attempt to aggregate the similarities and differences I've noticed, but I ...
2
votes
1answer
256 views

Detecting Key Loggers

We know that key loggers are the most effective and most annoying means of getting compromised over login id/password on the web or any application.... and your whole privacy is breached. Is there ...
4
votes
2answers
1k views

Known Password Lengths and security considerations

Many people wil often brag about the length of their password, like "yeah nobody is ever going to crack my password cause its 22 characters long." I was thinking, if you knew the exact length of their ...
9
votes
1answer
1k views

How to know the windows security dialog asking for username password is genuine?

I recently faced one issue. It appeared my outlook launched a dialog saying it needed password. It looked like this I noticed the "->" character in the domain name which usually it auto fills. Also ...
2
votes
1answer
252 views

How do we encrypt a password using another password?

An article on Kerberos goes like this: The problem is, Charon cannot give you the password directly, because then you would know it. [....] So instead of giving you the mail server's ...
14
votes
4answers
955 views

If a website allows another person to get a list of the site's users passwords, how likely is it that the passwords are stored in cleartext?

We had an incident where some of our managers were given passwords for the people they supervise using a particular company website. Ostensibly it was done so the managers could check in on the users ...
13
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2answers
214 views

Would suggesting a random passphrase during sign-up hurt overall security?

I've been looking for ways to improve security and security awareness for both internal and external clients and I happened upon the idea of generating a one-time, random "password suggestion" on the ...
4
votes
1answer
28k views

How long to brute-force WPA password?

Bob has a password (for his WPA encrypted wifi) which is 8 characters, all lowercase, and not a dictionary word. Eve lives next door to Bob and wants to illegally hack his WPA. The number of ...
12
votes
2answers
3k views

How secure is asking for specific characters of passwords instead of the entire thing?

In some password-authenticated sites, you are asked to enter a random selection of specific characters from your password rather than the whole word/phrase. For example, it might say 'Enter the 1st, ...
11
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2answers
3k views

Benefits and drawbacks of giving an Administrator two accounts for elevated rights and another for daily use, such as email

Microsoft has long promoted the need to separate administrative accounts from regular use accounts, as shown with this guidance MSFT even went to far as create ADMINSDUser rights to put ...
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3answers
918 views

It is possible that brute force attempts are successful before the worst case, correct?

When I read about a password being secure and stating that it would take X amount of week, years, etc. isn't that referring to the worst case? What happens if the brute force method is successul in ...
3
votes
3answers
2k views

what is the fastest and cheapest way to crack this kind of hash - md5(md5($password) + salt))?

I'm looking for a program that can use any GPU (ATI\NVIDIA) and can brute force a vBulletin hash - md5(md5($password) + salt)). I have the salt and hash. the password contains the symbols - ...
8
votes
4answers
810 views

Doesn't imposing a minimum password length make the password weaker by reducing the number of possible combinations?

I thought the strength of a password depended on the total number of possible combinations. Therefore, allowing longer passwords should be safer because you then have more possibilities. But why do ...
10
votes
3answers
1k views

Cryptographic Security of Dynamically Generated, Non-Random Salts

So when it comes to security, when I have an idea that seems good, but no one else seems to be doing, I try to assume that I'm overlooking something obvious or otherwise significant. This is one such ...
11
votes
2answers
381 views

How much security is compromised if we accept other characters as login (other than the original password)?

I've just realised that facebook accepts 3 forms of a password: Source: Facebook actually accepts three forms of your password: Your original password. Your original password with the ...
8
votes
4answers
3k views

Is forcing users to change passwords useful?

In many places, there's a policy that force the user changing it's password once a few months. The logic here is, that even if the password have leaked somehow, it'll be abused only for a relatively ...
61
votes
12answers
12k views

What to do about websites that store plain text passwords

I recently received an email from a popular graduate job web site (prospects.ac.uk) that I haven't used in a while suggesting I use a new feature. It contained both my username and password in plain ...
31
votes
2answers
12k views

I just send username and password over https. Is this ok?

When a user's logging in to my site, they send their username and password to me over https. Besides the ssl, there's no special obfuscation of the password - it lives in memory in the browser in the ...
2
votes
2answers
343 views

Company sending Master passwords in unencrypted emails

If a company has terrible security policies like letting people email password in cleartext emails, what to do if they reject all fair minded advice?
21
votes
2answers
3k views

Sending temp password when users first registered - is that good for anything?

One of our clients has sent us a list of security requirements. One of them was that registration does not including setting a password - once complete, a temp password is sent to the user, and the ...
10
votes
2answers
1k views

How should I make diceware passphrases more memorable?

I find that truly random diceware passphrase, more often than not, either contain a word that is easily misspelled or has an order that is illogical. I think there are three ways to make a diceware ...
20
votes
4answers
7k views

Deleting a Java Object securely

I know that in order to delete a Java object I should use character array instead of String, since I can safely erase (rewrite the character array with other data) its content. This seems not to be ...
3
votes
2answers
603 views

Can a survey website viewed in Firefox trick the user into sending stored passwords?

Firefox stores passwords (I am not referring to the Master Password feature) and I would like to know if a survey website can steal those passwords. I was typing a URL and perhaps I mistyped it and ...
1
vote
1answer
118 views

What function(s) to be used to generate Salt on Windows Mobile 6

I am looking for THE or a real function I can use to generate salt for my mobile app on Windows Mobile. In case I am not abusing in this request but in the future I plan as well the same app for ...
22
votes
4answers
4k views

How would you store a 4 digit pin code securely in the database?

I'm familiar with password hashing, using salts, bcrypt etc. But it doesn't seem like this would work to store a 4 digit pin code since the attacker could try all 10,000 combinations quite quickly. ...
4
votes
1answer
684 views

How can I manage multiple sets of passwords accessible by different users? [duplicate]

Possible Duplicate: Sharing passwords and credentials between founders and employees I use KeePass for my personal passwords. I would want to use it for my business, too, but the only way ...
6
votes
3answers
982 views

Attack vectors for brute-forcing website passwords

When talking about password security, a lot of discussion centers on the risk of a password being guessed in a brute-force attack. For websites where a user has registered an account, what are the ...
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votes
4answers
2k views

Brute-force heuristics used in password cracking

Existing questions on this site discuss some of the heuristics used by password cracking tools to avoid doing a completely naive brute-force search (for example, "dictionary word with number ...
6
votes
4answers
2k views

Password entropy in layman's terms

Entropy is a term used often in relation to password security and brute-force attacks, but it is a topic that can get complicated quickly. What is the best way to describe password entropy (what it is ...
9
votes
4answers
2k views

Passwords - any statistics on user behavior?

I'm looking for analyses of how users choose and use passwords. I'm sure there are many resources out there that analyze user passwords. For instance, I've seen many people analyze dumps of password ...
8
votes
5answers
451 views

Is there any added security benefit to username complexity requirements?

I've come across several sites lately that have complexity requirements for usernames like "must be 8 characters long and contain at least 2 numbers". Is there any real added benefit to this from a ...
45
votes
2answers
5k views

Pre-hash password before applying bcrypt to avoid restricting password length

Good practice is not to unnecessarily restrict password length, so that appropriately-long passphrases (perhaps 35-45 chars for 6/7 dicewords) can be used. (See e.g. Should I have a maximum password ...
9
votes
3answers
10k views

Security of passwords remembered by Windows

Does Windows XP or Windows 7 encrypt saved passwords? I'm assuming that the user uses local password to logon. The user then uses his own computer to connect to server in work and sets the "remember ...
25
votes
10answers
6k views

Best password strength checker

In XKCD #936: Short complex password, or long dictionary passphrase? Jeff claimed that password cracking with "dictionary words separated by spaces", or "a complete sentence with punctuation", or ...
12
votes
5answers
869 views

Should passwords be truly random?

When generating a password, should it be "truly random" or should I make it a little less random by enforcing some rules? If a password is generated at random, it could come out all-lowercase letters ...
34
votes
8answers
2k views

Who is responsible for the strength of user's passwords?

Who is responsible for a user's password's strength? Is it us (developers, architects, etc.) or the user? As a web developer, I've frequently wondered whether I should enforce the minimal password ...
22
votes
13answers
4k views

Why do we even use passwords / passphrases next to biometrics?

In the last couple of days there were a lot of talking about passwords and passphrases, not only here, but on several blogs and forums I follow (especially after XKCD #936 saw the light of this ...
9
votes
4answers
624 views

Are there state-of-the-art techniques or theory specifically for attacking passphrases over passwords?

With passphrases becoming more and more common based on length being more important than complexity, I'm assuming there must be some work going on involving techniques aimed specifically at cracking / ...
20
votes
3answers
3k views

Should I have a maximum password length?

I'm creating a webapp, and part of my authentication method is password length. Should I put one in place? (say, 50 characters?) Or should I just put a minimum length (Currently at 6). Are there ...
62
votes
21answers
16k views

How can I avoid my password being harvested by key loggers from internet cafes?

During traveling, especially in poor countries, sometimes you are going to need to use the internet at an internet cafe and you really can't be sure whether anyone has installed anything to listen to ...
15
votes
2answers
1k views

Are there some good papers (or discussions) on using Markov chains or Hidden Markov Models for password auditing/cracking?

As a programmer and language enthusiast I've been very interested in Markov chains for some time. Considering the influence of natural language on password and passphrase selection (by humans of ...
11
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2answers
2k views

Password auditing

Most password policies require the password to be at least 8 characters long and contain symbols from at least 3 classes (lower case letters, upper case letters, numbers, other). Problem is, that a ...
15
votes
2answers
3k views

Tamper-proof BIOS password & settings storage with Trusted Platform Module?

In the olden days, one could trivially bypass BIOS passwords on most PCs by removing the BIOS battery and clearing the CMOS. My question is: On modern PCs equipped with a Trusted Platform Module ...
6
votes
4answers
3k views

Are there lists of most common words or ngrams used in passwords and passphrases?

I've been thinking about ways to focus brute forcing dictionary attacks on passwords and passphrases based on the assumption that certain words, combinations of letters, and combinations of words are ...
6
votes
3answers
386 views

Are there password/passphrase guessers/crackers which can utilize facts supplied about the target?

I was just reading a discussion about cracking passwords that said the person running the tool might know things about the target like the birthday of his first girlfriend's dog but the tool won't. ...
6
votes
4answers
6k views

Are the iPhone “connect the dots” passwords secure?

A popular way to login to iPhones and other phones is to use a "connect the dots" password. For those unfamiliar, it looks something like this: Is this kind of passwords secure from brute force ...
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5answers
2k views

What password cracking software is commonly used?

I am curious to know how secure my passwords are. What password cracking software is commonly used? Preferably open source. EDIT: I am actually looking to crack my passwords used on services I ...
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5answers
3k views

How can I choose a strong password that is easy use on a smartphone?

Typing on a smartphone is tedious. Special characters are the hardest; lowercase letters are generally the easiest. But even a long all-letter passphrase like "correct horse battery staple" is ...