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

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1answer
763 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 ...
7
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4answers
906 views

Why does getting a password wrong takes more time than not

I type my password to login to Win or Linux. Case 1: I get it right. Almost instant reaction. Case 2: I misspelled it. It takes a while, and then rebounds. Why does it takes longer to identify a ...
7
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6answers
2k views

Is denying login after incorrect attempts ineffective?

Generally denying logon attempts after X amounts of incorrect attempts for Y amount of tries is a very basic way to prevent bruteforce attempts or malicous logon attempts. Yet, surely doing this is ...
7
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4answers
505 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 ...
7
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8answers
727 views

Is the following authentication scheme secure?

I was trying to design an authentication system that would make it much harder to guess a password via brute force, and reduce the risk to a user if the hashed password was stolen through a snooping ...
7
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3answers
558 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 ...
7
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1answer
763 views

Working out how to decrypt encrypted string when knowing the plain text

I have access to a system which I have been asked to create a data export routine for. However, the address details are encrypted and the original sourcecode/password are lost. However, I am able to ...
7
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4answers
4k views

How do online accounts get hacked?

How does your typical users run-of-the-mill Facebook/twitter/gmail/AIM/etc account get hacked? Is it simply a matter of a weak password? Are they typically the victim of phishing or other social ...
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6answers
513 views

Cleartext password in HTML

Is there any problem with outputing a user's password to the HTML in an hidden field (see use case below before flaming xD)? The use case is a registration form with two steps. The user fills in the ...
7
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4answers
939 views

How to protect ftp account information in the source code of a program

I wrote a game which stores high score information on an ftp server. In the the source code I need to write out the ftp link with the account name and password in it. For example: url = new ...
7
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4answers
505 views

Reasonable way to store encrypted passwords in a webapp's database, Linux

This question is generally similar to past questions asked here, but I haven't seen one the relates to Linux. Case at hand: a PHP web app has a MySQL backend. As part of its functionality it accesses ...
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6answers
1k views

Facebook account keeps getting hacked, can't seem to figure out why or how?

One of my mate, she has a lot of friends on Facebook, uses it for marketing. Her account keeps getting broken into. Her password gets reset and/or gets locked for changing resetting password too many ...
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3answers
507 views

Can cloud based password managing services be trusted?

I'm a big time user of cloud based password managing services like LastPass. But in the light of recent revelations like various government backdoors in popular sites, programs like prism, etc. I'm ...
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4answers
4k views

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
9k 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 ...
7
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2answers
472 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
2k 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, ...
7
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4answers
2k 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 ...
7
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2answers
446 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
4k views

Choosing a session ID algorithm for a client-server relationship

I am developing an application which has a client-server relationship, and I am having trouble deciding on the algorithm by which the session identifier is determined. My goal is to restrict ...
7
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3answers
222 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 ...
7
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3answers
1k 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, ...
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4answers
3k views

HTTP Basic auth password storage more secure than Digest auth

If you are using SSL already, it appears Basic auth is the way to go since you can perform bcrypt with the password when you store it in the database, where as Digest auth only allows md5. As we know, ...
7
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4answers
365 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 ...
7
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2answers
534 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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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 ...
7
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3answers
564 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 ...
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5answers
339 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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3answers
443 views

Should I obfuscate passwords before hashing? Should I pre-hash them on the client? What about salts?

For fun, and in my spare time I'm creating a simple CMS for my own purposes (with hopes to release for wider use... later), using PHP. I'm currently working on the login scheme now, and have a few ...
7
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2answers
465 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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4answers
648 views

Hash(master + hostname) password scheme for a server pool

I manage about 20+ Linux servers and I am considering using an md5 scheme similar to following to generate the admin passwords: echo 'masterpassword' 'serverhostname' | md5sum Which returns ...
7
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1answer
828 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
472 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 ...
7
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2answers
529 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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4answers
473 views

How can we factor Moore's law into password cracking estimates?

How would we go about factoring Moore's law into exceedingly long password cracking estimates? Let's say we've got a 12 character password containing mixed-case alpha characters and numbers, i.e. ...
7
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3answers
367 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 ...
7
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6answers
299 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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2answers
605 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
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 ...
7
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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
49 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 ...
6
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4answers
783 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 ...
6
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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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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
567 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
697 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
729 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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4answers
4k 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 ...
6
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4answers
522 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
272 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 ...