Contents
Does salt need to be random?
The only requirement of a salt is to be globally unique. It doesn’t have to be random and it most certainly does not have to be unknown. Note the keyword globally. A salt must be unique not only in the context of your database, but in the context of every single database out there.
Why should salt be chosen at random?
The salt must be random for every instance in which it is used. This ensures that an attacker has to attack every salted hash separately. If you rely on your salt (or salting algorithm) being secret, you enter the realms of Security Through Obscurity (won’t work).
Should I save the salt in database?
To stop them from precomputing hashes, the salt should be stored in the database, so they can’t get it before getting the hashes themselves, which means they need a lot of time to break the hashes after they compromise the database, which gives you a chance to change passwords before they get access.
How are salt used in the hashing of passwords?
Recap 1 A cryptographic salt is made up of random bits added to each password instance before its hashing. 2 Salts create unique passwords even in the instance of two users choosing the same passwords. 3 Salts help us mitigate hash table attacks by forcing attackers to re-compute them using the salts for each user.
How to generate salt in Java for salted-hash?
How do I generate a SALT in Java for Salted-Hash? 1 Generate a long random salt using a CSPRNG. 2 Prepend the salt to the password and hash it with a standard cryptographic hash function such as SHA256. 3 Save both the salt and the hash in the user’s database record. More
What happens if there is no salt in hashing?
Sees duplicate hashes. Attacker can arrive to conclusion that there’s no salts or using a weak algo to hash the passwords. If they find a lot of the same hashes, sign that server has a default password and every new acct has a default password.
What happens to the salt if you change your password?
1 Answer. If you do, salt will be unique per user, not per password, so if someone changes their password, their salt will stay the same. In which case, if there are database leaks at, say, three points in time, given that the salt is unique per user, not per password, the attacker gets some information about passwords (e.g.