Re[2]: MD5 Password encoding (was: Defeating Citi-Bank Virtual Keyboard Protection)

[Oleg Topchiy <edge () ua fm>]

Hello Noam,

Wednesday, August 17, 2005, 7:52:15 AM, you wrote:


> Hello Mike,

> If you are implementing a one-way hash correctly, there should be no need to
> store the plaintext passwords. All that should be stored is the resulting
> hash of each password.

> For example, if the plaintext password is, "secretpassword" the MD5 hash of
> that password would be, "31435008693ce6976f45dedc5532e2c1".

> That hash can be stored in the user database instead of a password. The
> advantage of this is that if the confidentiality of that database is
> compromised, no passwords will be revealed. There is no feasible way to
> reverse a one-way hash function to reveal the plaintext password.

> To authenticate users, you would take the user-submitted password (ex.
> "secretpassword") and perform the same hash function. The resulting hash
> should match the hash stored in the database.

It's true, but if the whole database is comporomised, there is a good
chance that vast number of the passwords won't stand against even
dictionary attack, leave alone bruteforce. Although this method
provides best balance between complexity and security.


-- 
Best regards,
 The.Edge                          mailto:edge () ua fm