Security Basics mailing list archives
RE: UNIX password auditing tool and the search for dictionaries too
From: "kenkousky" <kkousky () ip3inc com>
Date: Thu, 7 Aug 2003 09:51:31 -0400
Before you go too far with strong passwords, remember, they do more harm than good in most cases. You trust your money to a four digit pin so think about strong authentication, not strong passwords. Two factor can be done with a variety of inexpensive technologies. Strong passwords are the number one source of denial of service in most environments due to the frequent false reject problem that occurs when users can't keep up with frequent changes and strong password. They're also one of the highest costs for security since it's the number one task for help desks and sys admins to support. It's important to understand that most password attacks are not cracking the password encryption or hashes. In fact, that's still a very difficult task. The common password exploit on weak passwords is to run a large dictionary through the selected hash algorithm and then simple look up the captured hash values in the dictionary. A recent U of M exploit was a simple, inline keystroke logger. For the social engineer or thief, most desktops come with files on the desktop of passwords - beats the old post-it-note problem since most users simply have too many passwords for a single sheet of paper to work. The problem with weak passwords is mostly about using a weak handshaking, passing simple hashes rather than well encrypted passwords and keeping hash values accessible. In terms of dictionaries, I think the aggressive approach would include concatenations and number and special character injections into the words. In more secure environments, were users are battered with monthly password changes they usually inject the numeric value for the month somewhere in a common word. But the point is, it's not too difficult to build a really big database of words with special character and numeric injections, run them through the hash algorithm and have a table to check for matches. Dictionaries should also be modified for upper and lower case variations. I'd like to hear from others about the password vulnerabilities they're seeing in non NT server environments. "strong passwords are an oxymoron" KWK -----Original Message----- From: Shane Lahey [mailto:s.lahey () roadrunner nf net] Sent: Monday, August 04, 2003 7:38 PM To: james.easterling () ed gov; security-basics () securityfocus com Subject: RE: UNIX password auditing tool Alec Muffett Crack :: http://www.crypticide.org/users/alecm/
-----Original Message----- From: james.easterling () ed gov [mailto:james.easterling () ed gov] Sent: Monday, August 04, 2003 4:39 PM To: security-basics () securityfocus com Subject: UNIX password auditing tool I have tried searches for UNIX password cracking tools and I have come
up
with little value. Can someone direct me to passwd auditing tools besides "John The Ripper" that are free or cost? Regards, James
------------------------------------------------------------------------ --
-
------------------------------------------------------------------------ --
--
------------------------------------------------------------------------ --- ------------------------------------------------------------------------ ---- --------------------------------------------------------------------------- ----------------------------------------------------------------------------
Current thread:
- RE: UNIX password auditing tool and the search for dictionaries too kenkousky (Aug 07)
- RE: UNIX password auditing tool and the search for dictionaries too Michael Martinez (Aug 07)
- Re: UNIX password auditing tool and the search for dictionaries too Adam Newhard (Aug 08)
- more on strong passwords - a reply kenkousky (Aug 08)
- RE: UNIX password auditing tool and the search for dictionaries too Nick Owen (Aug 13)
- Re: UNIX password auditing tool and the search for dictionaries too Adam Newhard (Aug 08)
- <Possible follow-ups>
- RE: UNIX password auditing tool and the search for dictionaries too Tomas Wolf (Aug 11)
- RE: UNIX password auditing tool and the search for dictionaries too Tim Heagarty (Aug 11)
- RE: UNIX password auditing tool and the search for dictionaries too Mike Dresser (Aug 11)
- RE: UNIX password auditing tool and the search for dictionaries too Michael Martinez (Aug 07)