Full Disclosure mailing list archives
RE: Secure OWA
From: "Renshaw, Rick \(C.\)" <rrenshaw () ford com>
Date: Wed, 30 Aug 2006 11:00:18 -0400
-----Original Message----- From: Brendan Dolan-Gavitt [mailto:mooyix () gmail com] Sent: Wednesday, August 30, 2006 9:58 AM To: Renshaw, Rick (C.) Cc: Dude VanWinkle; Adriel Desautels; full-disclosure () lists grok org uk Subject: Re: [Full-disclosure] Secure OWA
On 8/30/06, Renshaw, Rick (C.) <rrenshaw () ford com> wrote:-----Original Message----- From: full-disclosure-bounces () lists grok org uk [mailto:full-disclosure-bounces () lists grok org uk] On Behalf Of Dude VanWinkle Sent: Saturday, August 26, 2006 2:30 PM To: Adriel Desautels Cc: full-disclosure () lists grok org uk Subject: Re: [Full-disclosure] Secure OWAThe only real fault I know about is the fact that you can guess passwordseternally without locking out user accounts. There's two sides to this risk. If you allow OWA logins to lock out accounts, and your OWA page is available from anywhere on the Internet, you are handing an easy DOS tool to anyone that knows the account names for people on your server.
Perhaps. But a temporary lockout period would deter brute-force attempts while still making an attacker do some work to keep the accounts locked (eg, if you have a lockout of 5 minutes, brute forcing is no longer practical, but at the same time, if you want to DoS someone's account you have to keep coming back every 5 minutes. And that increases the risk you'll get caught.)
-Brendan
My point was not matter which way you go on this issue, there is some risk. The only thing that you can do is balance one risk against the other and find the point where you feel comfortable with the risks. You could implement something like an exponential backoff wait between failed logins without lockouts, which would make it more difficult to brute-force the account, but there are ways around that too. At the end of the day, you have to pick which risk you are more comfortable dealing with, brute-force attacks or DOS attacks. Personally, I'd take the DOS, because it's better than allowing passwords to be brute-forced (in my mind). Rick
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Current thread:
- Re: Secure OWA, (continued)
- Re: Secure OWA <...> (Aug 26)
- Re: Secure OWA Dude VanWinkle (Aug 26)
- Re: Secure OWA Adriel Desautels (Aug 26)
- Re: Secure OWA Dude VanWinkle (Aug 26)
- Re: Secure OWA Valdis . Kletnieks (Aug 26)
- Re: Secure OWA Dude VanWinkle (Aug 26)
- Re: Secure OWA <...> (Aug 26)
- Re: Secure OWA Brendan Dolan-Gavitt (Aug 30)
- Re: Secure OWA Bardus Populus (Aug 30)
- Re: Secure OWA Mark Senior (Aug 30)
- Re: Secure OWA Brian Eaton (Aug 30)
- Re: Secure OWA Lohan Spies (Aug 31)