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What a collision is when using a hash function?
Definition: A collision occurs when more than one value to be hashed by a particular hash function hash to the same slot in the table or data structure (hash table) being generated by the hash function.
How do you handle a hash collision?
An alternative method for handling the collision problem is to allow each slot to hold a reference to a collection (or chain) of items. Chaining allows many items to exist at the same location in the hash table. When collisions happen, the item is still placed in the proper slot of the hash table.
Is this hash function collision resistant?
Cryptographic hash functions in general use today are designed to be collision resistant, but only very few of them are absolutely so. MD5 and SHA-1 in particular both have published techniques more efficient than brute force for finding collisions.
Can a hash collision attack on a password?
No, passwords are not vulnerable to hash collision attacks in the standard use of a password hash, where the hash is stored instead of the correct password and used to test a candidate password; that’s because the adversary is assumed not to know the password, and can not inject material in both hashed messages;
How to integrate hashing in the password storage workflow?
To integrate hashing in the password storage workflow, when the user is created, instead of storing the password in cleartext, we hash the password and store the username and hash pair in the database table. When the user logs in, we hash the password sent and compare it to the hash connected with the provided username.
What happens when two hashes of the same password?
Maps data of variable length to data of fixed length: meaning that the input message space can be “infinite”, but the output space is not. This has the implication that 2 or more input messages can have the same hash. The smaller the output space, the greater the probability of a ‘collision’ between two input messages.
Can a hash function be used to protect passwords?
A hashing function takes arbitrary inputs and transforms them into outputs of a fixed length. To qualify as a cryptographic hash function, a hash function must be pre-image resistant and collision resistant. Due to rainbow tables, hashing alone is not sufficient to protect passwords for mass exploitation.