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

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4
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3answers
1k 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 ...
6
votes
3answers
4k 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
809 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. ...
15
votes
11answers
4k 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 ...
13
votes
7answers
8k 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
1k 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
490 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 ...
20
votes
5answers
5k 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
199 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
votes
2answers
2k 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 ...
9
votes
1answer
2k 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 ...
-1
votes
1answer
178 views

How Does VMWare Protect Passwords? [closed]

I am interested what features VMWare uses to protect passwords inside the virtual machine.
3
votes
1answer
3k 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 ...
6
votes
7answers
15k 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
637 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 ...
11
votes
3answers
1k 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
634 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
767 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
712 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 ...
7
votes
2answers
5k 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 _). ...
8
votes
4answers
726 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
1k 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, ...
4
votes
11answers
4k 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
892 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
541 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
1k 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 ...
9
votes
1answer
959 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
118 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 ...
9
votes
2answers
856 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 ...
18
votes
2answers
5k views

How big should salt 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
3k 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
678 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
4answers
565 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 ...
4
votes
3answers
1k views

Why do some websites force users to come up with difficult passwords?

I can't understand why we commonly force users to come up with difficult to remember passwords. * Your password must contain at least one number, one uppercase character, and one special ...
1
vote
1answer
236 views

Can accounts still be logged onto if Password Caching is not enabled?

This is kind of an extension of my other question.. If you were not storing any of the passwords locally (caching disabled), would a user some how still be able to circumvent around this security ...
8
votes
4answers
2k views

Hacking computers, scifi or reality

I was watching The Girl with the Dragon Tattoo, and this female hacker was really good at hacking. My question is, how is it possible for her to crack passwords besides the brute force approach? I ...
7
votes
1answer
1k views

Bcrypt as a key derivation function?

I read a lot of entries at stack exchange about bcrypt and why it is supposed to be better than PBKDF2 in terms of password storage. I'm asking now if bcrypt is better than PBKDF2 in terms of key ...
21
votes
5answers
3k views

Is my bank storing my password in plain text? [duplicate]

My bank (and every bank I've come across) only ever asks for individual characters from my password when logging in. Is my bank storing my password in plain text?
3
votes
1answer
496 views

Best security algorith for storing passwords [duplicate]

Possible Duplicate: Which password hashing method should I use? I want the best cryptography algorithm for storing passwords in database, which one should I use and how can I implement ...
5
votes
2answers
3k views

openssl_digest vs hash vs hash_hmac? Difference between SALT & HMAC?

openssl_digest vs hash vs hash_hmac I want to use SHA512 for storing password. Which of the above methods are best to use? Why? What is the difference between SALT & HMAC? I just read ...
8
votes
1answer
478 views

Protecting emails in your database

It's common to encrypt passwords in the database, but I'm wondering what solutions are out there to protect emails in your database. Not just from hacking, but from disgruntled employees or engineers ...
9
votes
5answers
550 views

Utility company does not hash passwords in the database

I had to use my utility company's online account information application and forgot the password. Going through the steps of resetting the password I was emailed the password in the open. I found this ...
3
votes
1answer
3k views

What algorithm/encryption type does Gmail use for security?

In the wake of the recent database hacks, i.e. Sony, Gawker, etc.. where the hackers have access to the hashed usernames and passwords, i've been more keen in paying attention to the sites and ...
23
votes
5answers
3k views

Do spaces in a passphrase really add any more security/entropy?

I often see passphrase suggestions written as a sentence, with spaces. In that format are they more susceptible to a dictionary attack because each word is on it's own as opposed to a large unbroken ...
10
votes
4answers
9k 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 ...
10
votes
2answers
2k views

How does Google not care about “spaces” in Application-specific passwords?

I have recently setup "2-step verification" for my Google account. One of the features is the ability to create "Application-specific passwords " for devices that do not support the 2 step process. ...
2
votes
2answers
156 views

How can I protect a client's mirror of the server's database?

The scenario is as follows: There are clients that users can access and work with. These clients can be online or offline. There is a central database on a server, holding all the authorization ...
12
votes
3answers
17k views

Is a password protected PDF file safe for bank statement attachments?

My bank emails my monthly statement to me in a password protected PDF attachment. Is this a secure method of transmitting something as sensitive as bank statement?
4
votes
3answers
394 views

Is it safe or even common to cache bcrypt checks in-memory

In a web application that (as a side effect of implementing the password anti-pattern) stores passwords, one recommendation is to bcrypt to store them (or computationally expensive one-way salted ...