BCrypt is an adaptive cryptographic hash function for passwords. It incorporate a salt to protect against rainbow table attacks and is also an adaptive hash - over time it can be made slower and slower so it remains resistant to specific brute-force search attacks against the hash and the salt.

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Does bcrypt compare the hashes in “length-constant” time?

I saw this function slowEquals() while reading Salted Password Hashing - Doing it Right, which uses a byte-level xor comparison to avoid timing attacks. I was wondering whether this is what Bcrypt ...
1
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2answers
71 views

What is the real advantage of using a “more secure” algorithm like bcrypt for password hashing?

I read this article about password hashing using bcrypt as the recommended method. The advice is similar to what they're saying on hacker news about not using something like SHA2+salt. There are other ...
373
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5answers
122k 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 ...
10
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5answers
3k views

How to do client side hashing of password using BCrypt? [duplicate]

I am migrating an old application which used MD5 hashing to Spring Security with BCrypt encoding of passwords. I want to encode the password on new user creation page, change password page and on ...
14
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2answers
3k views

Insecure versions of crypt hashes

I read at crackstation not to use these variants of bcrypt* ($1$, $2$, $2a$, $2x$, $3$),but I've used bcrypt ($2a$) in various sensitive implementations recently. Can any security expert clarify why ...
321
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11answers
39k views

Is my developer's home-brew password security right or wrong, and why?

A developer, let's call him 'Dave', insists on using home-brew scripts for password security. See Dave's proposal below. His team spent months adopting an industry standard protocol using Bcrypt. ...
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2answers
96 views

Using a password hash…as the password? [duplicate]

Ok, this is probably a really stupid idea, but I can't really see why it would be a bad idea. Maybe someone can enlighten me. Why couldn't you enter a password good hashing algorithm like bcrypt, ...
38
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4answers
2k views

Is using bcrypt on existing SHA1 hashes good enough when switching password implementation?

I'm working on improving a CMS where the current implementation of storing password is just sha1(password). I explained to my boss that doing it that way is incredibly insecure, and told him that we ...
34
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3answers
13k views

Recommended # of rounds for bcrypt

What is nowadays (July 2012) the recommended number of bcrypt rounds for hashing a password for an average website (storing only name, emailaddress and home address, but no creditcard or medical ...
1
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5answers
838 views

Should BCRYPT be used for client-side password hashing

I am concerned about the use of bcrypt for client-side password generation. I am developing a password generation function to be used client-side, similar to PwdHash and PasswordMaker. Much has been ...
2
votes
1answer
29 views

How to go about password hashing when constrained to low work factor

I'm developing a social website as a side-project and seeing if it actually goes anywhere. I'm using bcrypt right now to store passwords and unfortunately I'm only able to get my webserver to do a ...
2
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3answers
227 views

Hashing passwords in OpenLDAP

I've seen a few posts on the internet saying most people store user passwords in OpenLDAP using one of OpenLDAP's many, built-in hashing functions. But OpenLDAP itself recommends handing off password ...
5
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2answers
589 views

Scrypt + Bcrypt = cascade hashing [duplicate]

I've read here that hashing with differents algorithms would be a good idea. Can you confirm that? In your experience, is it useful and safe? Does it entail any security holes?
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3answers
1k views

BCrypt's 72-character limit and using it as a general digest algorithm

Goal: have token/cookie-based authentication that doesn't require keeping sessions on the server TL;DR: What, if any, is the accepted mechanism to work around the 72-character limitation of BCrypt? ...
4
votes
2answers
855 views

What's the purpose of $LoginKey from the Ashley Madison leak?

According to this site Ashley Madison was keeping an insecure hash stored in their database using MD5, in addition to the far more secure bcrypt hash. This group used the MD5 hashes to quickly crack ...
10
votes
2answers
1k views

Why should I choose SHA (such as SHa-512), instead of bcrypt or PBKDF2, for FIPS-compliance?

Due to regulation, my company needs to be FIPS-compliant. I was looking at the current list of FIPS-approved cryptographical methods and I notice that neither bcrypt or PBKDF2 are in this list. ...
1
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1answer
91 views

Is it safe to use the SHA1 checksum of a password as a key for SHA-1?

I have an authentication system, where the passwords are stored with bcrypt hash (node passport module). My server generates a random key (128bytes) at startup. Whenever a user logs in, the server ...
1
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0answers
239 views

Storing Social Security Numbers in a Database

I'm developing an online application that needs the user's social security number. The application won't be processed on the web server so I'll be using an asymmetric key. So a compromised web server ...
2
votes
2answers
334 views

Practical steps for encrypting an encryption key for data stored in MySQL

So I'm working on my first project where user data is stored as encrypted using the user's password as (part of) the key. I have read many similar things about best practices, but the details seems to ...
3
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1answer
144 views

How to implement application-specific passwords using strong hashes?

I am implementing a service where application-specific passwords seem a good choice to improve security. A question on why and when they might make sense has already been discussed here Google ...
6
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1answer
267 views

What are the pros and cons of using sha256 to hash a password before passing it to bcrypt?

My apologies if this has already been asked. I recently became aware of the fact that bcrypt truncates passwords to 72 characters. Practically speaking my intuition is that this does not pose any ...
4
votes
4answers
877 views

Safety of Password Hashing Using bcrypt Done on Client Side

I am currently using a technique where I send the username/password in cleartext (using https) to the server, which then does bcrypt and compares to the db. Standard practice. It is considered safe. ...
21
votes
2answers
1k views

Can client-side hashing reduce the denial-of-service risk with slow hashes?

When storing user's passwords that you need to verify against (but not use as plaintext) the current state of the art is: Hash the password Use a salt Use a slow hash function - bcrypt, scrypt, etc. ...
5
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3answers
118 views

HTTP Server: Response time on login request

I have a site on which I would like to prevent an unauthenticated attacker from knowing if an account exists. On the site, passwords are hashed using bcrypt, so login requests must do a bcrypt ...
2
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2answers
375 views

Why is “\000” added to the end of passwords prior to hashing with bcrypt?

I am implementing bcrypt for java as found here. Before the actual hash takes place, line 455 of this implementation takes the raw String password, and transforms it into a byte array like so: ...
2
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3answers
248 views

Can I initially hash passwords with SHA instead of hashing them with bcrypt to decouple requests from slow crypto functions?

I'm using bcrypt for some web service requests that hash multiple passwords. The problem is that these web service requests can take minutes to complete due to bcrypt. Not very user friendly. My ...
3
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1answer
217 views

Securely storing passwords using PHP5

Starting note: After going through some articles and answers posted on SO related to storing secured passwords I'm still not sure whether my way of thinking is applicable to todays reality. I'm ...
0
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1answer
649 views

How does PHP's password_hash() BCRYPT cost factor translate into cracking computation times

I am trying to fully understand the relationship between BCRYPT's COST factors and how much more time it would take a machine to crack a password with PHP 5.5's password_hash() The encryption times I ...
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2answers
335 views

Do I need to set maximum characters length for password using bcrypt?

I using bcrypt to create a password hash and in the php documentation it says Caution: Using the PASSWORD_BCRYPT for the algo parameter, will result in the password parameter being truncated to ...
5
votes
2answers
165 views

which memory hard hashing algorithm can equalize low-computational and high-computational power devices to utilize blockchain in the IoT?

Recently IBM and Microsoft showed their interest (IBM post, Microsoft post) in utilizing bitcoin's blockchain for internet of things (IoT) development. Let's assume that in close future the blockchain ...
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1answer
425 views

What encryption algorithm does CryptEncrypt in Crypto API use?

I am writing a code to perform encryption and decryption using CryptEncrypt and CryptDecrypt functions, a part of Windows' Crypto API. Can anyone tell me what kind of encryption these two function ...
15
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3answers
6k 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?
4
votes
1answer
646 views

Is it a good idea to use two salts? [duplicate]

Is it a good idea to use two salts? This is implying that one would be unique to the user, and one would be unique to the server, using Bcrypt of course. So for example, if you're using Golang as ...
2
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2answers
209 views

Combining SCRYPT + a short crc

I'm considering using SCRYPT for password storage. (I'm open to PBKDF2 as well, or bcrypt by itself). The issue is that I don't want this to become a potential point for a DDOS attack, given the ...
2
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1answer
525 views

RESTful web application security and authentication scheme

I am building a web application where the front-end is a single-page-app and the back-end serves it through a RESTful API. I want to make sure I implement user authentication with the best security ...
0
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2answers
62 views

Using bcrypt in chrome extension [closed]

I am developing a chrome extension for this non profit. Im also working on the server side component as well. Im not a full time developer so most of my knowledge has simply come from years of ...
9
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2answers
2k views

“Official statement” on php.net : CRYPT_BLOWFISH is strongest hash algorithm. Why?

First: I asked this question on stackoverflow and was kindly asked to post this here again. See the original question here. According to the [early] doc pages of the new PHP 5.5 password ...
15
votes
6answers
5k views

Client side password hashing

Edit: Updated to put more emphasis on the goal - peace of mind for the user, and not beefing up the security. After reading through a few discussions here about client side hashing of passwords, I'm ...
1
vote
2answers
227 views

How does ASIC cryptocoin miners affect the security of scrypt?

Is the availability of these miners a reason to favor bcrypt (or something else) over scrypt? I mean, the goal of a password hash function is to maximize the work needed for an attacker to break a ...
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votes
1answer
119 views

What is the algorithm of bcrypt? [closed]

In many places I heard that people recommend to use the bcrypt algorithm to save passwords into database while creating web applications.I want to know what is the algorithm used to bcrypt a password ...
3
votes
2answers
180 views

Search on encrypted data of multiple users

I want to implement a search over encrypted data. I found a blogpost, which explains 3 methods. One method is to use deterministic encryption, which I'm trying to implement. But my use case is a ...
1
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2answers
960 views

HTTP Authentication with bcrypt done right

I have an android app that connects to a server through HTTP (notice the abscence of S, also android means Java, so nothing I'll hardcode in my app will be unreachable). I want to store the password ...
2
votes
1answer
97 views

Usefulness of bcrypt(UUIDv4())

One of my colleagues is working on securing OAuth 2 client IDs and secrets for our OAuth server and he has come up with this scheme where he would not only use UUID v4 to generate random values, but ...
1
vote
2answers
135 views

Is it unsafe to hash one password with more than one salt?

I'm asking my question here since I was not able to find an answer anywhere. I have written a piece of software which stores pretty delicate passwords. I have used BCrypt as hashing algorithm with an ...
28
votes
2answers
8k views

Does bcrypt have a maximum password length?

I was messing around with bcrypt today and noticed something: hashpw('testtdsdddddddddddddddddddddddddddddddddddddddddddddddsddddddddddddddddd', salt) Output: ...
1
vote
1answer
177 views

I know scrypt is newer than bcrypt, but is there any reason it would be weaker?

From what I read, scrypt is (on paper) more secure than bcrypt, but it's pretty new so it's better to let it get time-tested and scrutinized first. However, is there any good, compelling reason to ...
6
votes
3answers
513 views

Is it good practice to SHA512 passwords prior to passing them to bcrypt?

I want to allow any-sized passwords to be allowed to be submitted. I currently use bcrypt as a key derivation function for passwords, however I have realized that it has a maximum input length of 72. ...
0
votes
4answers
2k views

Is salted MD5 or salted SHA considered secure?

Is using something like bcrypt or scrypt necessary? The hashes are so much longer to store in a database. Can one get away with using salted MD5 or SHA and still be secure?
3
votes
1answer
4k views

The brute-force resistence of bcrypt versus MD5 for password hashing?

Can anyone give me an idea? Assume the salt(s) is/are known. For example, if I have a $k$-character long password that is hashed in MD5 versus bcrypt, is there a way to estimate how much more time it ...
10
votes
4answers
2k views

Does the strength of password matter in bcrypt?

Even if I choose 1 character for my password or 32 characters with numbers, letters, uppercase symbols etc. the bcrypted password will still be 60 characters length password. So does the password ...