Linked Questions

15
votes
7answers
1k views

To salt, or not to salt? [duplicate]

Possible Duplicate: Why is using salt more secure? Why would salt not have prevented LinkedIn passwords from getting cracked? Recently I decided that I wanted to learn more about web security, ...
45
votes
2answers
28k views

How Does A Random Salt Work? [duplicate]

I don't understand how using a random salt for hashing passwords can work. Perhaps random salt refers to something other than hashing passwords? Here is my thought process: The salt is used to add ...
0
votes
1answer
148 views

if salt stored in user, will it be possible to use brute force attack? [duplicate]

I had done a lot of research about this topic. Before Researchs I found that some people suggest that to hide salt is not important: https://crackstation.net/hashing-security.htm But also this ...
610
votes
5answers
252k views

Do any security experts recommend bcrypt for password storage?

On the surface bcrypt, an 11 year old security algorithm designed for hashing passwords by Niels Provos and David Mazieres, which is based on the initialization function used in the NIST approved ...
144
votes
3answers
66k views

What are rainbow tables and how are they used?

Where can I find one? Is there a pot of gold at the end? How do I protect against them? From the Area51 proposal This question was IT Security Question of the Week. Read the Sep 09, 2011 blog ...
79
votes
5answers
76k views

How does hashing work?

I have been interested in Information Security. I was recently introduced to the idea of hashing. What I currently understand about hashing is that it takes the password a user enters. Then it ...
43
votes
4answers
16k 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 salt?...
18
votes
6answers
8k views

Which password policy is more secure: one password of length 9 vs. two passwords each of length 8?

What is more secure, having one password of length 9 (salted and hashed) or having two different passwords, each of length 8 (salted and hashed using two different salts)?
24
votes
6answers
13k views

Do salts have to be random, or just unique and unknown?

First of all, my motive is to avoid storing the salt in the database as plain text. As far as this question is concerned, the salt is not stored in the database. After discussion in comments and in ...
25
votes
5answers
10k 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. ...
24
votes
3answers
14k views

Is a HMAC-ed password is more secure than a bcrypt-ed or scrypt-ed password?

Given an option , which one should I choose , a HMAC for storing a password securely or a bcrypt or scrypt library?
21
votes
2answers
9k views

Why is it always `HASH( salt + password )` that we recommend?

Browsing over this site, many forums, online articles, there's always one specific way we're suggesting to store a password hash: function (salt, pass) { return ( StrongHash(salt + pass) ) } But ...
8
votes
8answers
4k 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 ...
11
votes
4answers
1k views

How can I be secure with a global salt?

If I understood the basic of password hashing and storing, what we need are: a "strong" salt a "real" random salt a unique salt per password a password hashing function with a high CPU cost We hash ...
1
vote
4answers
4k views

Shall I need to use MD5 algorithm in both JavaScript and PHP for login authentication?

I have a login form with username and password. I post this form data to a PHP file. For security reasons I want to encrypt my password in the database and network. Now I have done now following steps....

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