What can a rainbow table be used for?
A rainbow table is a database that is used to gain authentication by cracking the password hash. It is a precomputed dictionary of plaintext passwords and their corresponding hash values that can be used to find out what plaintext password produces a particular hash.
How does the reduction function work in rainbow table?
So that the required storage space doesn’t get out of hand, rainbow tables use a reduction function that change the hash value into plaintext. Important: The reduction function doesn’t reverse the hash value, so it doesn’t output the original plaintext (i.e. the password) – because this isn’t possible – but instead outputs a completely new one.
How is a hash function used in a rainbow table?
A hash function is a 1-way function, which means that it can’t be decrypted. Whenever a user enters a password, it is converted into a hash value and is compared with the already stored hash value. If the values match, the user is authenticated. A rainbow table is a database that is used to gain authentication by cracking the password hash.
How is a rainbow table used for authentication?
Whenever a user enters a password, it is converted into a hash value and is compared with the already stored hash value. If the values match, the user is authenticated. A rainbow table is a database that is used to gain authentication by cracking the password hash.
How are hash values determined in a rainbow table?
In a rainbow table, this takes place not only one time, but many times, resulting in a chain. In the final table, however, only the first password and the last hash value of a chain appear. Based on this information and taking the reduction functions into account, all other values can also be determined.
How does a rainbow table speed up password cracking?
A rainbow table is a precomputed compilation of plaintexts and matching ciphertexts (typically passwords and their matching hashes). Rainbow tables greatly speed up many types of password cracking attacks, often taking minutes to crack where other methods may take much longer (e.g., dictionary, hybrid, and brute-force password cracking attempts).