Re: Detecting Brute-Force and Dictionary attacks

In message <9555a4b00611080922u79c38d7dl8a7132cb7f299ec2@xxxxxxxxxxxxxx>,
"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 <Cy.Schubert@xxxxxxxxxxxx>
Web: http://www.komquats.com and http://www.bcbodybuilder.com
FreeBSD UNIX: <cy@xxxxxxxxxxx> Web: http://www.FreeBSD.org
BC Government: <Cy.Schubert@xxxxxxxxx>

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