[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date: Thu, 16 Oct 2014 14:34:25 -0600
From: Kurt Seifried <kseifried@...hat.com>
To: oss-security@...ts.openwall.com
Subject: Re: attacking hsts through ntp
On 16/10/14 01:45 PM, Hanno Böck wrote:
> Am Thu, 16 Oct 2014 09:56:06 -0600
> schrieb Kurt Seifried <kseifried@...hat.com>:
>
>> The obvious solution being to whitelist your site (in the
>> chrome/firefox source code)if you truly care:
>
> No.
>
> While this is neat (and I already did this for my most important
> domains) this won't help.
>
> The reason: HSTS preloaded sites are handled exactly the same way as
> normal HSTS sites - they can expire. Chrome sets a maximum timeout for
> HSTS of 1000 days for preloaded sites. That was elaborated in the talk
> today. He demonstrated the attack on google mail which is in this
> whitelist. Set clock 3 years into the future and youre done.
I did not know that. One concern I have is also HSTS has no tools to
manage them in browsers, at least when I last checked, has that changed?
There is some room for DoS due to this on the client side.
> It could be argued that it is wrong to expire preloaded HSTS sites. But
> the very same attack applies to HPKP which basically has to expire,
> because you don't want to use keys forever.
If people say "I use HSTS, so much so that I want you to whitelist it IN
the source code forever" I'm pretty sure they never want it to expire
(at least that was my thought when I got my domains whitelisted).
--
Kurt Seifried -- Red Hat -- Product Security -- Cloud
PGP A90B F995 7350 148F 66BF 7554 160D 4553 5E26 7993
Download attachment "signature.asc" of type "application/pgp-signature" (820 bytes)
Powered by blists - more mailing lists
Please check out the
Open Source Software Security Wiki, which is counterpart to this
mailing list.
Confused about mailing lists and their use?
Read about mailing lists on Wikipedia
and check out these
guidelines on proper formatting of your messages.
