Re: Detecting Brute-Force and Dictionary attacks

In message <[email protected]>, 
"Seba
stiaan Veenstra" writes:
> Hi,
> 
> I didn't read the whole discussion about this issue but I came up with
> an idea which might be usefull to detect brute force attempt. By
> storing the passwords a certain user has used in the past along with
> the current password you could be able to compare to password (by
> pattern matching) used at the login attempts with the passwords list.
> If the password used differs significantly (this excludes typos) from
> the entries in the password list, there could be a possible brute
> force attempt. The reason for storing the previous passwords is that
> people tend to use every password they've used in the past when they
> forgot their password. Maybe this idea can be used along with the
> other methods of detecting brute force attempts. Anyway, it's just a
> random thought.

In many jurisdictions this would be an invasion of privacy and against the 
law. Not only that but a security exposure too. For example, people tend to 
use similar passwords, even the same passwords for various applications and 
machines. Once a sysadmin knows someone's password the victim could be 
impersonated without detection. Whereas su commands, access to Oracle 
databases, and other services the sysadmin would not normally have access 
to would require work on the part of the sysadmin to gain entry into and 
these attempts would surely be logged and hopefully detected. Logging 
people's passwords is a bad idea.


-- 
Cheers,
Cy Schubert <[email protected]>
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