Questions tagged [bcrypt]
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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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 ...
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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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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 ...
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Why improvising your own Hash function out of existing hash functions is so bad
I'm afraid I'll have tomatoes thrown at me for asking this old question, but here goes.
After reading that cooking up your own password hash out of existing hashing functions is dangerous over and ...
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Are there more modern password hashing methods than bcrypt and scrypt?
This question made me start thinking about password hashing again. I currently use bcrypt (specifically py-bcrypt). I've heard a lot about PBKDF2, and scrypt.
What I'm wondering is if there are any "...
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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 ...
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Does bcrypt have a maximum password length?
I was messing around with bcrypt today and noticed something:
hashpw('testtdsdddddddddddddddddddddddddddddddddddddddddddddddsddddddddddddddddd', salt)
Output: '$2a$15$jQYbLa5m0PIo7eZ6MGCzr....
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In 2018, what is the recommended hash to store passwords: bcrypt, scrypt, Argon2?
There are many questions about picking a hash function, including How to securely hash passwords? or Are there more modern password hashing methods than bcrypt and scrypt?, with very detailed answers, ...
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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 ...
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How to apply a pepper correctly to bcrypt?
Update: There is a better way to add a server side key, than using it as a pepper. With a pepper an attacker must gain additional privileges on the server to get the key. The same advantage we get by ...
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What is the specific reason to prefer bcrypt or PBKDF2 over SHA256-crypt in password hashes?
We know that to slow down password cracking in case a password database leak, passwords should be saved only in a hashed format. And not only that, but hashed with a strong and slow function with a ...
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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.
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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 ...
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Is bcrypt(strtolower(hex(md5(pass)))) ok for storing passwords? [duplicate]
I have a large database where passwords are stored as strtolower(hex(md5(pass))) (which is a bad way to store passwords, prone to rainbow tables, cheap to dictionary attack, no salt, etc.),
and I'm ...
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Is it possible to increase the cost of BCrypt or PBKDF2 when its already calculated and without the original password?
I just wanted to know if you can increase the cost (iterations) of those two algorithms off-line.
I want to increase the cost every year of my users passwords.
One solution is to recalculate them when ...
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How is storing an API secret key in plaintext (in a database) secure?
The answers to this question Is it okay for API secret to be stored in plain text or decrypt-able? are somewhat unsettling to me. I'm trying to wrap my mind around how storing a secret key in ...
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Challenging challenge: client-side password hashing and server-side password verification
We have a website where users need to log in to access privileged information. Obviously we are using SSL, but I also want to avoid plaintext passwords from accidently ending up in server logs, or ...
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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 ...
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Does Rehashing a weak hash with a strong algorithm make it strong?
Imagine the following situation. We're making a web application which should be really safe
Now the accounts/users are not directly added by us but they receive a letter with a logincode. We get a ...
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Is it possible to decrypt Bcrypt encryption? [duplicate]
I do have password that has been encrypted with Bcrypt and the salt . Is it possible if I want to decrypt the password into normal text ?
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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 ...
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Security of bcrypt/sha256 key used with AES to encrypt a file
I'm looking to encrypt files using secure hashing and encryption algorithms in Python. Having used bcrypt in the past, I decided to use it for my passphrase calculator, then pass the output through ...
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Is bcrypt better than scrypt [duplicate]
Possible Duplicate:
Do any security experts recommend bcrypt for password storage?
I'm no security expert and do not pretend to be that's why I'm asking here. I write many PHP based applications ...
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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?
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bcrypt no need to store salt?
I'm confused with bcrypt, I would think I would need to store my salt, and then compare my plain text password + salt to the hashed password, however from documentation it does not look like storing ...
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Should you care about DoS attacks if your server is using bcrypt?
(I just asked this question on "cryptography SE" and was suggested to ask it here instead)
EDIT I just realized my question is mostly a dupe of: Prevent denial of service attacks against slow hashing ...
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How secure is BCRYPT(SHA1(Password)) [duplicate]
This question is a fork from a previous question here:
Is it safe/wise to store a salt in the same field as the hashed password?
Assume you run a web portal, and store passwords in SHA1 hashes. How ...
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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 ...
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How can I make sure password hashing is secure on computers while not being prohibitively slow on mobile devices?
I'm new to cryptography and its implementations. I'm designing an Android app where an user enters a password to retrieve some encrypted data. After some research on possible solutions I ended up with ...
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How should I choose a difficulty factor for my password hashing function?
Assuming that I'm doing password hashing properly and using bcrypt, scrypt or PBKDF2, how should I go about choosing an appropriate difficulty factor? i.e rounds for bcrypt, iterations for PBKDF2 and ...
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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.
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Does NIST really recommend PBKDF2 for password hashing?
We hesitated between BCrypt and PBKDF2 for password hashing. In many forums and blogs people say something like "In their Special Publication SP 800-132 NIST basically recommends using PBKDF2 for ...
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Estimate the time to crack passwords using bcrypt
I am reading on the Ashley Madison password exposure case. Dean Pierce was able to output about 4000 cracked passwords within 5 days given his system. I'm assuming that he generated a table of hashes ...
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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.
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Explain BCrypt like I'm 5
I know this is a little bit broad, but I'd like to understand the function of this algorithm by explaining like I'm 5. And I'd like to know the difference between BCrypt and blowfish, is it because ...
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Client-Side Hashing to decrease value of password guessing heuristics
Yes, this is 'yet another client-side hashing' question. But, don't leave yet, I think there is some value here.
I'd like to do something to mitigate the affect on the community as a whole when my ...
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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, ...
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Is BCRYPT easy do decrypt?
I know that bcrypt doesn't encrypt, but how easy would it be to get the password from a stored bcrypt hash?
I wanna split my question about bcrypt into 2:
I read over here that bcrypt generates ...
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Is it possible to get hacked if my bcrypt hash is publically known?
I just checked https://haveibeenpwned.com/ and I have noticed that I was pwned, therefore I checked the file that hosts the details of my "credentials", however, I see my email in plain text but the ...
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How secure is this hash-based personal password scheme? [duplicate]
I use a password scheme where I keep a small number of easy to remember personal passwords. Instead of using the passwords directly for each service, I run them through a hashing algorithm first, as a ...
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What are the pros and cons of using sha256 to hash a password before passing it to bcrypt?
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 major security problems. However, I understand ...
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bcrypt: random salt vs computed salt
I'm pretty new to the whole password hashing business, so I might be missing something obvious.
I was looking at the bcrypt algorithm, in particular BCrypt.Net, and I was wondering if it wouldn't be ...
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Is there a table that compares hashing algorithms by speed, relatively (machine independent)
As far as I understood*, one of the major criteria when choosing a password / salt hashing algorithm is it's speed. To prevent brute force attacks, a slower algorithm is better (and also makes it more ...
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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?
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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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How is a pepper used with salted passwords?
How is a pepper (a large constant number) used after a password has been salted with a salt by a hashing function such as bcrypt?
From Sybex CISSP Official Study Guide, 8th Edition (2018):
Adding ...
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Is it safe (or a good idea) to advertise the use of bcrypt?
So, our database is using bcrypt with a high iteration/cost to store our users passwords. We're using https like intelligent people and we continue to work on finding ways to sidestep our own security ...
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Are bcrypt hashes safe enough if exposed?
Considering:
A VERY motivated attacker,
A large entropy password, as in 256bits¹ hashed in bcrypt (with recommended cost factor of 12), and
Attacker knowledge of everything he might need (except the ...
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Would multiple exposed bcrypt hashes of the same UUID v4 with random generated salt be too insecure?
I'm looking into implementing an ownership check on JSON objects and want to avoid going back to the database to ensure ownership of said object/record (i.e., to prevent a user from updating an object/...
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What can someone do with a Google auth token?
I just received an email from "Have I been pwned" to say my credentials have been made public via a breach. The quoted text is:
"The exposed data included names, email addresses, genders, spoken
...
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