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

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Regulations that specify password length?

I have read: PCI DSS 1.2 SOX 404 AR 25-2 ISO 27001 But only PCI DSS specifies a minimum password length. Are there any other regulations that dictate password lengths for any industry? NIST ...
7
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3answers
10k views

With ASIC bitcoin miners, should SHA256 be considered insecure for password hashing?

I'm sure everyone here has seen the rise and further rise of bitcoin. The process used for mining bitcoin is basically "let's brute force an SHA256 hash that is less than this amount" That being ...
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3answers
2k views

I don't see how “-salt” in the openssl command line tool enhances security at all

I do this to encrypt a single file: openssl aes-256-cbc -a -salt -in file.txt -out file.enc and then type in some regular plaintext password. I do not understand how -salt enhances the security of ...
7
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2answers
556 views

Should user be allowed to save password in browser?

The auditing company found a bug "The Auto-complete form attribute is set in password field". They suggested to disable autocomplete for this field to prevent disclosure of it "when working on shared ...
7
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4answers
3k views

How to implement a “Remember me” on a mobile app?

I would like to implement a "Remember Me" time-limited auto-login type feature on a mobile application (on Android). To start the app, the user must type in a username and password. For convenience, ...
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3answers
341 views

Increase the security of an already stored password hash

Right now we're using 1024 byte PBKDF2 with 256 byte user-specific salt and variable iterations. However, I would much prefer to be able to, perhaps once every year or two, to be able to flat out ...
7
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2answers
537 views

How to proceed if a new hash algorithm for passwords is introduced?

I have an e-mail address at a certain institution. A few days ago they sent me an e-mail (in German), which I'd like to paraphrase without revealing the institution: Dear Madams and Sirs, a ...
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3answers
228 views

Should I restrict access to the username and passwords in a web app?

I'm starting to write my first serious web application and am thinking about how to store username and password information. There are plenty of articles detailing how storing plain text passwords is ...
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3answers
2k views

Is HTTPS and Basic Authentication secure enough for banking webservices (RESTful)?

I have been reading about SSL/TLS for the last few days and looks like it has never been practically cracked. Given SSL/TLS is used for all communications between client application and the server, ...
7
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2answers
574 views

Replacement for One Time Passwords (OTP)

OTP may known as new generation of password security techniques, but I want to know does it still safe enough after several years of appearance or it will deprecate soon? & what would be the ...
7
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4answers
376 views

Will passphrases always be secure?

In a world where most people used passphrases instead of passwords, wouldn't an attack that generates a random string of words (alternating between word delimiters) be similarly effective to a brute ...
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1answer
1k views

How will security need to be changed if P=NP?

If we suppose that it is found that P=NP, how will security measures need to be changed? I'd like to know the major security measures that are affected, and how they would need to be changed. We can ...
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3answers
684 views

Is it secure to use bcrypt-generated salt in cookie to serve as token in place of a password?

I have a (hobby) web site that runs only on SSL. The site does not deal with finances, social security numbers, or anything of that level of importance. However, I'd like to secure it as much as ...
7
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2answers
540 views

Should an admin user be able to edit passwords?

For your typical web app, should an admin superuser have the right to edit a user's password, or should only that user have the right? (Even with edit ability, the admin would never see the current ...
7
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5answers
348 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 ...
7
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1answer
859 views

Would it make sense to use Bcrypt and PBKDF2 together?

I've read various opinions about whether Bcrypt or PDBKF2 is a better key derivation hashing method. The answer seems to depend on a lot of complicated factors that are not easy to analyze. Would ...
7
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5answers
491 views

Are we concentrating too much on password complexity?

As a developer and/or user, do I really need to worry about password strength if the system does not allow brute force attack to be feasible (implements a delay or attempt counter) or implements a ...
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3answers
7k views

How to crack password hashed using SSHA?

Is it possible to crack a password hashed using SSHA if I know the salt? How can I do it?
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2answers
3k views

Why limit passwords to ascii printable characters? [duplicate]

Possible Duplicate: Do non-keyboard characters make my password less susceptible to brute forcing? Every article on password security that I read tells people to make the password more ...
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2answers
650 views

Are the SS64.com password generators a good approach?

There are two password generators on ss64.com: The standard one The strong one How they work I made standalone versions of them, plus copy of the original HTML/Javascript versions, if you want to ...
7
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1answer
618 views

Reversible password storage obfuscation method for third-party login credentials

I have an internal business application, that as part of its functionality connects to a third-party app using login credentials specific to the user of my own app. These passwords are stored in a ...
7
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3answers
384 views

Is it advisable to have a web browser remember login credentials?

I have a really long random password for my cellphone account and have it written down in a safe place. I only use it once a month and am considering having my browser remember it. Would there be any ...
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6answers
305 views

City Government Emailing User Name and Password

My city has online billing for utilities. When you set up an account they email your user name and password to you. You can't change your password without them emailing it to you again. Isn't this ...
7
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4answers
191 views

What standards are there for mangaging high value passwords?

I am leading a small team at a start-up and I am facing a dilemma with high value passwords. I am the only one on the team who knows all the key passwords for production servers, databases ... etc. ...
7
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2answers
643 views

Encryption Algorithms with an error code for wrong password

I am looking for an encryption algorithm that would allow me to know if the password supplied is the correct one or not. This question can be considered as a follow-up for Q. In particular the answer ...
7
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1answer
708 views

When taking ownership of a TPM in Windows 7, how is the SRK derived from the password?

When you take ownership of a TPM in Windows 7 you encounter a screen like this: Based on this document, it is my understanding that completing this dialog box somehow results in the generation of ...
7
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1answer
261 views

How to stop password recovery attempts on accounts?

I am using social networking services such as My Banking GMail PayPal Facebook Twitter Google+ LinkedIn All of these services text messages me a six digit code to login from anywhere, even a ...
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1answer
1k views

Store user passwords in NoSQL database?

I am currently coding the backend of a website and I have not come across an article where this is discussed. I want to store all my application data in MongoDB but I'd like to split out my sensitive ...
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3answers
1k views

How does LastPass' grid multi-factor authentication work behind the scenes?

I understand how to use the Grid multi-factor authentication as a user but how does it work technically? Specifically how can just a few letters from the grid be enough to decrypt any secret defined ...
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0answers
54 views

What do studies show are best practices for password expiration policies? [duplicate]

Possible Duplicate: How does changing your password every 90 days increase security? What are best practices for password expiration policies? There are some questions that already address ...
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4answers
1k 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 ...
6
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4answers
904 views

Password hashes should run md5 thousands of time: really?

I skimmed through How Companies Can Beef Up Password Security and I thought that several assertions were completely wrong, in particular: Cryptographic hash (like md5) with salt are bad. It isn't ...
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8answers
1k views

Does truncating the cryptographic hash make it impossible to crack?

I store password hashes in their full value for example, $h = sha256('foo') outputs 64 characters: 2c26b46b68ffc68ff99b453c1d30413413422d706483bfa0f98a5e886266e7ae I store that directly in the ...
6
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7answers
600 views

How easy is it to find a password in a huge text file?

Say that my password is PASSWORD1 I have a 10MB jumbled text file. I hide my password in two parts in the text, between > and < so I can find it myself. Then I put the 2 parts together and add the ...
6
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5answers
780 views

Is storing plaintext passwords for email accounts any less bad? [duplicate]

I recently found out that the company I use for shared hosting stores passwords for email accounts in plaintext (they mentioned this to me incidentally, while troubleshooting another issue). They're a ...
6
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7answers
745 views

How can I prevent users from using bad passwords in my web application?

There is a long discussion on whether it's the responsibility of the user or the system administrator to deal with the strength of the password. Obviously, the password is a very private thing, but ...
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10answers
1k views

How to easily remember lots of different passwords?

I know that you shouldn’t use the same password on every site. But, when you log into several dozen sites, keeping track of all the passwords can be pretty hard. What system do you recommend that ...
6
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5answers
526 views

Creating multiple secure and easy to remember passwords

I have recently developed a new web application which our clients log into using a username and password. As we're just rolling out this system, we'll be setting the usernames and passwords ourselves, ...
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4answers
5k 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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4answers
698 views

Why using random salts?

I read this blogpost on how to store passwords in a database, the secure way. Elbert tells us to do this: Generate a random salt and include something random and the username in it. Hash this. Hash ...
6
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3answers
290 views

How much added security do I really get with a longer key size?

Imagine I have a cipher which supports keys of 128, 192 or 256 bits. Suppose that there are no vulnerabilities in the cipher regardless of key length. I'm going to use it to encrypt something, and ...
6
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3answers
332 views

How can Microsoft validate a shorter password on Microsoft accounts (MSDN)?

I recently ran across this when logging into MSDN. (I saw this screen after typing my initial credentials.) I have a 20+ digit password, however there's apparently a new requirement for Microsoft ...
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2answers
2k views

Dictionary Attack on Wifi

I know a few people with pretty weak passwords. What kind of systems exist to prevent dictionary attacks? Would it make sense to restrict the number of connection attempts in a certain timeframe? ...
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5answers
4k views

How can I avoid putting the database password in a perl script?

I have a cronned perl script that connects to our database and does various kinds of lookups and integrity checks. The original script was written by someone long ago. My job is to make some changes ...
6
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2answers
703 views

Is it better to hash n*x times in sha1 or n times in sha512 on the client side?

I already know I"m going to hash the user's password n times in either sha512 or n*x in sha1 before it is sent to the server. Once at the server, I'm going to use bcrypt set to use ~1/100th of a ...
6
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6answers
15k views

Recommend Length for Wi-FI PSK?

I currently have a network set up with WPA2 and AES encryption, the password is 8 characters long but was randomly generated and contains no dictionary words. However I'm concerned about the ...
6
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3answers
204 views

Would secure storing of past used/generated passwords be a good idea?

Let's assume an organisation that generates ~100 Passwords a week; these Passwords are 32-Characters long and randomly generated. The consultants that need passwords generated use a Password-generator ...
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3answers
2k views

HMACSHA512 versus Rfc2898DeriveBytes for password hash

We are currently using HMACSHA512 in .net, with a 128Char (64byte) validation key The salt is 64 char randomly generated string. We allocated 2048 length on the database for the hashed base64 string ...
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3answers
2k views

Can ssh keyfile security be broken in a few hours if the file is exposed?

At this link there is a claim that if an RSA key has a strong passphrase security might be broken in a few hours if an attacker has the private key. Is there something weak about the security of RSA ...
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3answers
271 views

Should password be cleared after unsuccessful logon attempt?

Lets assume following workflows a) On a device with keyboard: I type my username and password Press enter [realization] I made a typo Password field is cleared: not a big deal, I can type ...