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

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1
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1answer
167 views

Stripping / appending characters from user password before hashing to conceal it forever?

I had this idea to permanently conceal user password by requiring minimum length then stripping certain characters. For example if the user password is secret123, the system will strip it down to ...
3
votes
2answers
516 views

Can key files be brute-forced like passwords?

Let's say you use a program like Truecrypt or Keepass which allows you to have a password + key file. I understand that passwords can be brute-forced/dictionary-attacked but is the same true for key ...
5
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2answers
236 views

Are more passwords breached via dictionary/bf attacks or via packet-sniffers/key-loggers?

This question has always intrigued me whenever the subject of passwords is brought up. Does anyone have direct experience or a reputable source to answer what percentage of password breaches are ...
8
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3answers
3k views

What are the risks of storing passwords in a GPG encrypted file?

I currently store my passwords in a text file encrypted using GPG -e (specifying my own public key). When I want to lookup a password I'll do something like gpg -d passwords.gpg | grep ...
4
votes
4answers
626 views

Do password complexity requirements reduce security by limiting search space?

I've read that password complexity requirements make passwords easier to guess via brute force attack. The reason for this is that the complexity requirement actually reduce the search space for brute ...
-1
votes
1answer
222 views

What time do dictionary attack take on salted passwords?

I was reading that the designers of UNIX password algorithm used a 12 bit salt to modify the E-table of the unix hashing function (the DES). Supposing i have a system with 2^(24) users? Is that ever ...
5
votes
3answers
150 views

When form submission fails, password field gets blanked, why is that the case?

I've recently asked a question about blanking the password fields in UX for usability purposes, but It seems all the sites use this approach for security reasons. Why is it insecure to post back the ...
2
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0answers
132 views

Lastpass - Can I just keep the previous autofills? [closed]

I just installed the Lastpass Firefox plugin, and it seems like a useful tool thus far. The only thing that drives me crazy is that I am used to the Firefox saved passwords where it will show the last ...
19
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4answers
2k views

Why is using salt more secure?

Storing the hash of users' passwords, e.g. in a database, is insecure since human passwords are vulnerable to dictionary attacks. Everyone suggests that this is mitigated via the use of salts, but the ...
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4answers
148 views

pesudo random password

I post a question before about one password repeating to make it longer, now its a new way want to ask about, if take the word 'secure' and instead of repeating it put somenumbers between it, exp: ...
7
votes
4answers
366 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 ...
8
votes
6answers
753 views

Does repeating one word to form a password result in a similar pattern in its encrypted format?

If i use a single word to form a password by repeating it like the examples below: securesecuresecuresecuresecuresecure SeCuReSeCuReSeCuReSeCuReSeCuReSeCuReSeCuRe ...
1
vote
2answers
394 views

Using a tabula recta to store passwords

Reading an answer to another question ("Is there a method of generating site-specific passwords which can be executed in my own head?") I came across this link, describing a way to use a physical ...
6
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3answers
1k 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 ...
0
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1answer
156 views

Securing communication

The problem: I have an open-source client (a Firefox add-on written in JavaScript) and a server containing somewhat sensible user information: username and user history (all from YouTube). The client ...
12
votes
3answers
2k views

Password in file .php

My connection.php file stores the credentials to connect to the database. <?php $objConnect = mysql_connect("localhost","username","password"); mysql_select_db("selectDB", $objConnect); ...
3
votes
3answers
580 views

Are Three attempts to block login a good idea?

In the company that I work there is a security rule: If you enter your password 3 times wrong, your login will be blocked! Then I have to go to mainframe program and re-register my new password. ...
19
votes
5answers
1k views

Is it alright to tell everyone your encryption information?

I have an account in an online banking system and they have the FAQ with something like this: How secure is the <Online Banking System Name>? Each page you view and any information ...
5
votes
3answers
2k views

What are some good ways to verify user identity for password resets?

I'm wondering how others verify the identity of users they're resetting passwords for. We currently try to speak to a manager at work, but it frustrates end users and seems like we don't trust them. ...
14
votes
3answers
596 views

What can I do if my bank thinks my date of birth is “known only to me”?

My bank has recently replaced passwords with occasionally asking me information that is "known only to me". Such information includes my date of birth, postcode, and my mother’s maiden name. ...
14
votes
11answers
2k views

Best practice for password distribution

I am about to set up a new account on my Linux server for a user that lives in another state in the U.S. I can't think of a good way to get them this user their password. There must be a standard ...
10
votes
6answers
4k views

Forgotten password or reset link, which is more secure to email?

I originally posted this as a reply here in this thread but didn't get much feedback on it, and now I'm curious as to what others think is the best approach, or if there is any difference between the ...
4
votes
1answer
785 views

Why does Windows 7 require a password hint during setup?

Correct me if I am wrong, but I think Windows 7 is the only operating system out there that requires a hint for the first user created on the system (have not had a chance to check out Windows 8 ...
2
votes
1answer
353 views

How can wireless router password encrypts data using WEP and WPA

How does the password that we enter (to connect to a wireless network) encrypt the data on the wireless network? Through my reading I am not sure if the password that we enter is the same as the ...
18
votes
5answers
3k views

What's the practical limit for rainbow-table based bruteforce?

Say we have a hash of a password. The password can be considered to be made of of totally random characters and has a fixed length of N. The hash is SHA1(password+salt), where the salt is of length M. ...
2
votes
2answers
179 views

What are stolen passwords used for?

Say there is a line of business application which has username/password datatable in the DB. Personal email address is not stored, and usernames are assigned by an administrator. Someone gains access ...
6
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2answers
1k views

Considering that SRP is better than SSH and Basic Auth, how can it be implemented in a website?

SRP is short for Secure Remote Password protocol, and provides a better way for passwords to be sent over the internet. I've read the information at it's Stanford University home page, the Wiki ...
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 ...
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1answer
165 views

How Does VMWare Protect Passwords? [closed]

I am interested what features VMWare uses to protect passwords inside the virtual machine.
3
votes
1answer
2k views

Please explain Time-step in Time-Based One-Time Password Algorithm

I am studying about OTPs (One Time Passwords). I have gone through all the methods: HOTP (HMAC-based One Time Password), TOTP (Time-based One Time Password) I have no issues with HOTP. But according ...
5
votes
5answers
7k views

Is a longer WiFi password more secure?

Today I had to type the same password to connect to a WPA2-secured WiFi network several times, and got really annoyed with the length of the password. Especially since it is just a phrase repeated ...
5
votes
5answers
411 views

What are all of the issues with storing a cleartext password?

I know, I know, cleartext passwords are terrible and you should always store a hash! However, I'm interested in all of the issues with storing cleartext passwords so I can make a reasonably secure ...
7
votes
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 ...
10
votes
3answers
525 views

How can I promote good password practices in an organization that doesn't currently care about that?

I work with an organization that uses some very poor practices such as using default user accounts, default passwords (or passwords the same as user accounts), sharing password information between ...
2
votes
3answers
572 views

What is the recomended algorithm to create a key from a password?

In my new secret document encryption utility, the key for symmetric encryption = the hash of a random salt and a user provided password. It is necessary to have a slow hash function in order to ...
9
votes
5answers
649 views

Using a weak password on a truecrypt volume

I have put together a portable apps USB stick for when I need to use random site computers, I also threw truecrypt on with an encrypted volume for some word documents. The password I am using is ...
4
votes
2answers
3k views

How expensive is it to guess a 15 character password, and should I be worried?

I'm currently using AES encryption (at home) on GNU/Linux (one of LUKS AES-256 variants with xts) and on Windows 7 (Truecrypt) with a 15 characters password (alphanumeric lowercase only plus _). ...
7
votes
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 ...
3
votes
1answer
774 views

How to implement WSS UsernameToken when password on the server is salted and hashed?

I'm currently trying to write a web service for customer and requirement is to use WS Security. On their server side, they have passwords stored as SHA-1(salt+password). According to WSS spec, ...
3
votes
11answers
3k views

Definitely safest password storage scheme?

I already asked this on StackOverflow but I was suggested this would be a better suited place and I found no way to "move" the question so I have to copy it. Believe, I know, there are hundreds ...
3
votes
2answers
614 views

Efficient and simple way of securing home pc with hardware token

I am looking for a simple but reasonably safe way to secure my home pc (and laptop, nas, etc.) with a hardware token. I would like the system to be secure, but practical enough to be used on a day to ...
6
votes
3answers
406 views

Is it OK to use the same password for a Linux login and the SSH private key?

I want to remotely log in to my Linux server with SSH. Public/private key authentication is more secure than password authentication, so I have disabled password-based authentication for SSH on my ...
2
votes
6answers
891 views

“Double hashing” with 2 different hash functions

Is doing something like this sha256(sha512(password+salt)) Less secure then just doing sha256(password+salt) I've heard it will increase collision chances. I can think of 3 reasons to do this ...
7
votes
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 ...
4
votes
0answers
107 views

Dealing with systems that store/send passwords in plain-text [duplicate]

Possible Duplicate: What to do about websites that store plain text passwords When using a system as it was designed to be used, and the system provides proof that it is storing and/or ...
7
votes
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 ...
10
votes
2answers
2k views

How big salt should be?

I will be using scrypt to store passwords in my application. As such, I'll be using SHA-256 and Salsa20 crypto primitives (with PBKDF2). Having that in mind, how big salt should I use? Should it be ...
4
votes
3answers
2k views

Reverse-engineering one-time passwords for two-factor authentication systems

Given a one-time password generator that is time-based (such as Google Authenticator), how many instances of (time, PIN) pairs would one need to significantly weaken the algorithm to a point where one ...
2
votes
1answer
543 views

Token Based Authentication & Pass-the-hash Attacks

Do token-based authentication solutions (such as RSA SecurID) mitigate tools like incognito and/or pass-the-hash tools?
11
votes
5answers
391 views

What is the best way to hand out passwords to a widely spread diverse employee base?

I have a problem I need to solve - specifically, how to hand out passwords to people in a variety of locations, and with a wide variety of access. I've thought of some options, but there are ...