Full Disclosure mailing list archives
Re: Firefox 2.0.x: tracking unsuspecting users using TLS client certificates
From: Peter Besenbruch <prb () lava net>
Date: Fri, 07 Sep 2007 07:31:59 -1000
With apologies to Alexander. I keep forgetting that replying to full disclosure messages sends an e-mail to him, and not the list. Here is my reply to the list: Alexander Klink wrote:
... I realised that you can do something with Firefox 2.0.x that you could not do with Firefox 1.5.x: track an unsuspecting user using TLS client certificates.
...
Proof of Concept: - http://0x90.eu/ff_tls_poc.html
So, one can use certificates as a kind of super-cookie. You mention in a follow-up message that all kinds of information can be stored in a certificate. With cookies, a third party advertiser can place a cookie and track you across sites, building up a profile of your interests. While I can see the same use here, it seems you are saying anyone could have a look at certificates on your system, while cookies generally are limited to viewing by the issuing domain. What I don't understand is if there is a simple of knowing what certificate to ask for? For this to be useful, that would be pretty important. Another question, is it possible to issue a "give me all your stored certificates" command? The follow-on link to Apache's cert-export page can't seem to do that. I made two certs and the cert-export page grabbed that last one. Oh well, time to change Firefox's default certificate handling. -- Hawaiian Astronomical Society: http://www.hawastsoc.org HAS Deepsky Atlas: http://www.hawastsoc.org/deepsky _______________________________________________ Full-Disclosure - We believe in it. Charter: http://lists.grok.org.uk/full-disclosure-charter.html Hosted and sponsored by Secunia - http://secunia.com/
Current thread:
- Firefox 2.0.x: tracking unsuspecting users using TLS client certificates Alexander Klink (Sep 07)
- Re: Firefox 2.0.x: tracking unsuspecting users using TLS client certificates Eddy Nigg (StartCom Ltd.) (Sep 07)
- Re: Firefox 2.0.x: tracking unsuspecting users using TLS client certificates Alexander Klink (Sep 07)
- Re: Firefox 2.0.x: tracking unsuspecting users using TLS client certificates Eddy Nigg (StartCom Ltd.) (Sep 07)
- Re: Firefox 2.0.x: tracking unsuspecting users using TLS client certificates Brendan Dolan-Gavitt (Sep 07)
- Re: Firefox 2.0.x: tracking unsuspecting users using TLS client certificates Peter Besenbruch (Sep 07)
- Re: Firefox 2.0.x: tracking unsuspecting users using TLS client certificates Alexander Klink (Sep 07)
- Re: Firefox 2.0.x: tracking unsuspecting users using TLS client certificates Arshad Noor (Sep 07)
- Re: Firefox 2.0.x: tracking unsuspecting users using TLS client certificates Erik Tews (Sep 07)
- Re: Firefox 2.0.x: tracking unsuspecting users using TLS client certificates Eddy Nigg (StartCom Ltd.) (Sep 07)
- Re: Firefox 2.0.x: tracking unsuspecting users using TLS client certificates Alexander Klink (Sep 07)
- Re: Firefox 2.0.x: tracking unsuspecting users using TLS client certificates Alexander Klink (Sep 07)