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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Argon2 is worse than bcrypt at runtimes < 1000 ms? [duplicate]
While Argon2 seems to be recommended for password hashing, based on this twit Argon2 is worse than bcrypt at runtimes < 1000 ms.
Based on this answer:
You should tweak the parameters to your own ...
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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 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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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 it secure to expose a salted bcrypt hash IF it is maximum length random secure password?
Is it secure to expose a salted bcrypt hash (minimum 14 cost) if the used password is 72 characters (maximum) byte long, randomly generated letters, numbers, and special characters using secure ...
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Is it a good practice to add hard-coded salt to BCrypt passwords?
I am currently learning about cybersecurity and trying to implement it in my next web application.
I have been reading some articles about hashing, specifically SHA2 and Blowfish.
In this article, it ...
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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 ...
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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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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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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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Best practices for storing passwords for PHP and MySQL applications [duplicate]
I am creating a simplified lead and call management system for a friend's small business.
I would like to know the best practices for hardening password storage and verification using PHP 7.4 and ...
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Why is the BCrypt text "OrpheanBeholderScryDoubt"
I'm looking for a reference about the weird initial BCrypt text "OrpheanBeholderScryDoubt"
Why was this string used?
Would using 192 zeros or ones not have worked well in practice for some reason?
...
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Hash collisions in password history
When a user changes password, I'd like to implement a simple check that prevents them from reusing the same password. If the new password matches the old password, reject with an error.
Sounds easy, ...
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Base64 encode differences in BCrypt implemenations
I was reading the source code of several BCrypt implementations and found that two common c implementations have a difference in their base64 encoding of the salt.
What is the effect, if any, of the ...
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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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Is client-side bcrypt sent over tls + server-side sha hmac secure for password storage?
I want to hash passwords for security, but strong bcrypt by nature eat up a bit of resources of the server. So I was thinking to do the encryption on the client side. This would prevent the password ...
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How do I properly secure my login using bcrypt in react and a python-flask backend?
I want to store the passwords of accounts hashed into a database that can be accessed through a python-flask application. When you would login, this python application is supposed to provide you with ...
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How many rounds of Bcrypt to use for security equivalent to SHA256?
We regularly use 10000 iterations of SHA256 for hashing passwords.
If we want to have similar security, how many rounds/work factor should we use when hashing passwords with bcrypt?
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What maximum password length to choose when using bcrypt?
When I generated password for GitHub with KeePass I got a message on GitHub site that said the limit for password length is 72 characters. It seemed weird it not being a power of 2 so I googled a bit ...
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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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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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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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Is it possible to reverse a hashed password? [duplicate]
Is it possible to reverse a password hashed with bcrypt?
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Best secure approach with Basic Auth
Due to several customer reasons our product needs to support Basic Auth as primary authentication mechanism with client's service account.
We are using Bcrypt to store customer's password in our DB, ...
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How can I use a unique salt for each user
I know there are various questions that seem similar, for instance, this one. However, it does not answer my question.
I'm creating a signup/login system (with node.js to be particular), and I'm ...
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How can salted passwords work if you don't "keep the salts in the system"?
In this report on the recent ParkMobile breach, the article has this comment from the company:
“You are correct that bcrypt hashed and salted passwords were obtained,” Perkins said when asked about ...
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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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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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Having a list of hashes for the same password compromise the security of the password?
An attacker want's access to a specific account, he doesn't know the password.
It's a high entropy password. +128bits
The attacker has the hash for the password (Assuming OWASP suggested bcrypt with ...
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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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If the bitcoin network was cracking bcrypt, what cost factor would you use?
Since the best example of pooled resource to crack hashes is the bitcoin network, currently churning through 2.14 ExaHashes/s.
I want to ask, if the resources of this network were pointed towards ...
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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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Is using SHA256 to create 256bit secret key from bcrypt good ok?
I am trying to Use AES to store passwords for a password manager. For authentication I am already using bcrypt. As AES uses 256 bit Key can I use SHA256 to generate 256 bit key from hashed value of ...
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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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How is the bcrypt algorithm decrypted? [duplicate]
I have a ton of hashed texts and their decrypted or de-hashed forms (I don't know which term is suitable in this case) via bcrypt. The thing I want to learn is how they are decrypted.
For example, the ...
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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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Search by hashed value [closed]
I would like to design a REST API endpoint (POST) that takes in some sensitive identifier information in the request body:
{
"someDataToSearch": "abcdefgh"
}
I then want to ...
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Is it possible to use Argon2id hashes with PAM?
I was wondering if it's possible to implement more secure KDF like bcrypt, scrypt, pbkdf2 and argon2id in PAM authentication.
Ideally I would like to have their hashes instead of SHA-512 ones directly ...
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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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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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Any reason I shouldn't be salting and hashing before putting through bCrypt?
I've been reading up on password storage and such, and have come to the conclusion that I need to be using bCrypt.
I've got an implementation working correctly, but I'm wondering the best way to move ...
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Incrementing Work-Factor of Hash Functions Over Time
For a long time hash functions have required a work-factor in order to keep the operation "slow" enough to protect individual passwords in the case of a database leak. Bcrypt and PBKDF2 being notable ...
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Is single iteration SHA-256 safe enough for hashing 128bit random number API keys?
I implemented this kind of authentication for my REST API, is this secure and is my logic sound?
I am primarily curious about the SHA-256 hash & iterations = 1 aspect. I have omitted some details ...
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Is chain hashing algorithms the ultimate solution for hashing passwords?
Let's say I my password is a simple password, 123456
Then if the database was exposed, if the password was:
-- stored in plain text -> cracked
-- stored it hashed with no salt -> prone to rainbow ...
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How authenticate a login with javascript
I want to authenticate a user using a username and password in a web app running javascript interfacing to a non node js or php server. In a normal desktop app I could use bcrypt or an hmac or ??. ...
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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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Can you help me with some misconceptions about bcrypt and salting?
I researched password hashing and cracking and I have some misconceptions:
First rule of thumb to create a strong password is to use 10+ combination of digits/upper/lower/symbols to prevent brute ...
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Encryption and decryption in the browser on the client's side – is it safe?
There is a possibility to download the file with one’s PII from the dedicated web server. The file might be decrypted by filling the two factors. These two factors are delivered via email and SMS. The ...
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BCrypt vs PBKDF2-SHA256
I read that LastPass uses PBKDF2-SHA256 for storing the Master Password hash, I wonder how this compares to BCrypt and why did they chose this, as SHA256 is a quick hash (probably compensated by PKDF2?...
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Is it safe to encrypt a user's third party API key with their own password?
I'm running a node application which needs to make calls to a third party API, on behalf of my user, using their own API keys.
API calls only need to be made on behalf of the user while they are ...
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