Questions tagged [passwords]
Passwords are secret keys which human beings can memorize.
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Concatenation of password and TOTP - possible issues
I have come across a two factor login mechanism using Time based OTP (TOTP). TOTP (6 digits) is shown to the user in an app.
There are two ways of logging in.
Method 1:
User inputs the username and ...
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Is there a quantum-safe password-based authentication method that doesn't require giving the server too much data
I've been reading up on different authentication protocols recently while I implemented the sign-in functionality for my website. Many of the suggested methods password-based authentication seem to ...
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Password Manager Architecture and Design
I'm working on a local, client-side password manager. I want to hash a master password with argon2 to store it safely in an SQLite database. This will be how a user could login and be authenticated. (...
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How secure is the password from the hash sum (SHA-512) of a long sentence
If I convert a long sentence (>50 characters) to c and use the result (128 hex characters) as a password, how secure is it?
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Can you have a public password file that is still secure?
So I’ve been reading about different ways to store passwords on servers (plain text, encrypted, hashed, hashed + salt, slow hash + salt) and I wanted to find a way where a leak of the stored passwords ...
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Transmit a password to inheritors
I am looking for a safe and easy way for my inheritors to get a password after my death. That can be the password of a digital vault, a password manager, or anything else.
I could write the password ...
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Is it true that 7zip doesn't use any salt with its KDF?
This issue claims that 7zip does not use any salt with its key derivation function: https://github.com/magnumripper/JohnTheRipper/issues/1679
If that's true, wouldn't that mean you can crack multiple ...
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Is 7-Zip Encryption really secure? [duplicate]
Is 7-Zip really a good encryption tool? I wonder what kind of encryption is used in 7-zip. I see most people using 7-Zip. Just curious about what extent it is safe.
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Cache-hard or memory-hard password hashing algorithms?
bscrypt is a cache-hard password hashing algorithm/KDF from Steve Thomas (aka Sc00bz/TobTu), who was on the Password Hashing Competition (PHC) panel. He argues it is better than the alternative ...
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Generating Complex Passwords from (Non-)Memorable Phrases - Need Advice
I've been thinking about creating strong and unique passwords for my online accounts, but I also want them to be memorable. I've come across the idea of using a memorable passphrase as the basis for a ...
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Why don't basically all "clusters" and similar distributed systems use Shamir's secret sharing method?
When I came to the topic of Ansible (Vault), when deploying secrets in Ansible and other passwords up to 128 characters Shamir's Secret Sharing would be an ideal solution I think:
The secret is never ...
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The state of Shamir's Secret Sharing in 2023
Shamir's Secret Sharing GPL implementation called ssss got removed from Tails OS years back.
Is Shamir's secret sharing still secure nowadays? Why was it removed ...
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who creates the passkey (and how many will be created)? [closed]
Passkey is nice. The math is nice. The tech is nice. https://security.googleblog.com/2023/05/so-long-passwords-thanks-for-all-phish.html
What I still dont see after sooo many hours: what software ...
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Impersonation attack on Lamport's one time password
So here I am, googling my brain on the possibilities of impersonation attempts by a MITM attacker on Lamport's one-time password scheme.
Here's my scenario:
Say we have a client and server setup. ...
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Can limited password/PIN length be compensated by a computationally intensive hashing function?
Say we have a very limited password space with only a 4 digit PIN, so only 10000 PIN possibilities.
Say also that the attacker has access to the stored form of the PIN.
Can breaking the PIN be made ...
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Is using slow password hashing on the client side easier attackable than on the server side?
As we know, one should use a slow password hashing algorithm instead of a fast one for storing passwords, to hinder brute force attacks when the database is compromised. The problem with this is that ...
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How many bits should change in a password salt?
In https://crypto.stackexchange.com/a/27828/79037, it's indicated that one can "save space" by using something globally-unique, like an application-wide "pepper", together with ...
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Is sha3 a one-way funtion
If i store sensitive stuff (e.g passwords, salted passwords, Internet protacel adresss(so i know its not tamperd with), private keys(the keys are using a portion of the key on multiple disks in ...
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Academic papers for the pros and cons of password based system and digital signature with challenge and response system
I don't really know what should be the correct title for this and the community can correct it after reading.
I was the author of PKDSA (Searchable on github).
I have the idea to do it because I feel ...
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Best practices on implementing a password manager
I'm a dev new to security and cryptography.
I'm writing a password manager and Time-based OTP combo in dart/flutter to use in multiple devices and platform for fun and use it personally for real. I ...
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Is hashing salt possible even with the password with salt appended to the end?
Should you hash the salt on its own ? Is that possible?
for example being password with salt appended at the end hash(pass || salt) and hash(salt) in a password file?
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Is it possible to sign in to a website using two different passwords using an MD5 hash collision?
I wanna do an experiment. I wanna see if it's possible to sign in to an outdated website that still uses MD5 to store passwords (there are surprisingly still a lot) with two different passwords.
For ...
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Using 32 hexadecimal digits vs equivalent 16-character string password
Assume I'm using a cryptographic algorithm to pseudo-randomly generate a string that is specified to be 16 characters long. The string will be used as a passphrase when encrypting a file.
So, for ...
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Can using an unknown, non uniform random salt increase difficulty for password attacks?
I remember reading a previous stack exchange post (unfortunately was unable to find the link, if someone knows the link that would be great!) about a method to make password checking time for the ...
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Key management in Java + Remembering passwords
I'm new within the area of crypto so I apologise if I am bad at explaining this. So correct me if I've misunderstood anything.
I'm currently developing a Java Fx application that includes the use of a ...
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Use name as the initialization vector to encrypt passwords for users
I'm using AES-256-CBC to encrypt password for a set of users, and for each user in the database we gotta generate and store the password in the database. The ...
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How long does it take to crack PBKDF2?
How much time will it take to crack PBKDF2 while using a 9 character password? I'm not specifying any specific system or platform. If a brute force attack is made using the best ever super computer ...
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How to calculate probability of cracking a password from entropy?
I am working on a project for my maths assessment where I research the effect of complexity and length on a given password. Currently, I am working on calculating the probability of guessing a ...
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Remembering user credentials by double-hashing
I'm developing a desktop application where the users will login with username and password, which is then verified against a database. After the initial login, the current user should be automatically ...
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How long would it take all of the supercomputers or cloud computing on Earth to bruteforce a significantly long password?
I was arguing with a colleague who thinks that SHA256 (password + 64 character static salt) is "insecure." My argument is that nothing in cryptography is "secure," it's all a ...
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Higher encryption, means less strong password required?
Does higher encryption mean that my password could be shorter? If the time to decrypt is longer, then the chance to bruteforce gets lower too, right?
I've created a KeePass database, and at the ...
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Do I need to use a CSPRNG when creating salts for user accounts?
I'm not sure about the need of using CSPRNG to create salts for each user account.
I found “Cryptographically Secure Pseudo-Random Number Generator in Qt/C++ (Cross platform)” (at StackOverflow) with ...
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Hashes to passwords with PBKDF2
If an attacker wants to hack the passwords of $2^{10}$ users. And all of these users generate a password from the space of $2^{50}$ passwords** and each password is hashed with PBKDF2 with $2^{10}$ ...
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Designing a scheme to store encrypted data on a backend
My goal is to design an encryption scheme for the application so that the backend stores encrypted data and the whole process of encoding and decoding happens on the frontend. And you can be sure that ...
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Number of characters in 64-bit and 128-bit password
I have a simple question but I can't seem to find the answer of.
I know that
A 128-bit hash contains 32 characters since each represents a hexadecimal.
Similarly, a 64-bit hash would contain 16 ...
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Sending password to server vs. sending SHA
This is an existing website with approx. 100K accounts, and passwords are hashed using bcrypt with a high number of rounds.
The current design that I'm questioning is that we're sending the username ...
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How strong are Bitlocker recovery keys?
This is an example of a bitlocker recovery key;
820042-335825-646573-481530-265253-688132-339900-822810
İs that key actually strong? It does not have any letters, ...
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Why does SHA-256 have any to do with scrypt?
I was reading the Wikipedia page for scrypt because I wanted to learn more about it and I came across their pseudocode for the algorithm. What confused me was the following line:
I don't understand ...
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How does biometric authentication add protection to encryption schemes?
I'm wondering since at least 2 offline password management services,Passkeep and Keepass both use biometric authentication in addition to the master password. You need to possess the physical device ...
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Benefit of salt in KDF like Argon2
I don't understand why I need a salt for Argon2 if Argon2 is only needed as a KDF for a password which is then called AES. At the end neither the password nor a password hash is stored. Only the data ...
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Password Hashing based on Common Passwords
If an attacker has a database of 1,000 users' hashed passwords which are hashed with SHA-256 with a 128-bit salt and all of these users used 10,000 common passwords. How many hashes will the hacker ...
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Password space: number of possible password combination
How do I calculate the password space of a randomized linked hybrid pasword of 9 images and 10 numbers(0-9)? User allowed to select 4 password
Images=9
Pin= 0-9
Password selection allowed: 4
Every ...
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Password hashing and salting with SHA-256 on $2^{64}$ password space
If a password is randomly chosen from a space of $2^{64}$ passwords and is stored as an SHA-256-bit hash and a 128-bit salt, how many hashes does an attacker need to perform to recover the password in ...
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How many hashes to recover a salted password? [closed]
If a password p is selected from a space of 2^64 passwords, and the server stores this as a hash, h = SHA-256(p||s) where s is a random 128-bit salt. How many maximum hashes would an attacker need to ...
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Algorithm used to generate a BitLocker recovery key
I know exactly how a generated BitLocker recovery key works and I can write a code to brute-force it.
How is the recovery key generated though?
I could think of some answers:
it is generated using an ...
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KEY using AES-128, If P is less than 128 bits, padded with 0 and create 128 bits, any problem if average pw length is 6
For communication between the client and the website, use password (P) as the key using AES-128. If P is less than 128 bits, it is padded with 0 to create a 128 bits key. is there any problem with ...
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Password encryption in database
I want to store passwords in a database in a way I can reuse them to authenticate users (symmetrical encryption).
I read some good information here: https://cheatsheetseries.owasp.org/cheatsheets/...
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Debug bcrypt iterations with a static salt [closed]
I want to debug bcrypt rounds with a static salt using this python lib
...
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Base64 or hex to attach auth tokens to URL?
I just came across this question, but it does not really answer my main concern that I have regarding password tokens.
To authenticate a client who is not logged in; I generate two random tokens and ...
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How easy is it to identifiy the key when knowing a certain number of different AES-256/Fixed Nonce encrypted long-integers
Given some intervals of long integers (64 Bits). I need to generate alphanumeric strings which:
should be used like passwords(known only by few individuals)
must always be the same for the same ...
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