amiljkovicFeb 26
The Ars article mentions: “Even when HTTPS is in place, an attacker can still intercept domain look-up traffic and use DNS cache poisoning to corrupt tables stored by the target’s operating system.” Not sure, but I think this could then be further used for phishing.
Show threadjcalvinowens
DNSSEC prevents that if set up properly.
Feb 26 at 7:49pmWeb
Show threadtptacekFeb 27
This is an on-path attacker. In end-user DNS configurations, attackers can simply disable DNSSEC; it's 1 bit in the DNS response header ("yeah, sure, I verified this for you, trust me").
Show threadjcalvinowensFeb 28
No, modern resolvers like systemd-resolved actually check the dnssec signatures on the client.
Show threadakerl_Feb 28
Can you link to a distro config that defaults to that?
Show threadjcalvinowensFeb 28
No, it's experimental. But I run it on all my machines, the only time I've had a problem is when it caught a typo in a DS record.
Show threadtptacekFeb 28

Nobody has ever disputed that you could run a fully recursive cache on your workstation, only that any ordinary user ever does.

You can see at this point how hollow "DNSSEC" is as an answer to the problem of this thread.

Show threadjcalvinowensMar 1
It's not a full recursive lookup: you don't understand how DNSSEC works. I'm not replying to you any more.
Show threadtptacekMar 1
I'm guessing I do. Anyways: no question that there are a variety of experimental setups in which you can address the problem of on-path attackers trivially disabling DNSSEC, freeing you up to work on the next, harder set of DNSSEC security and operational problems.
Show threadtptacekFeb 28
To check the DNSSEC signatures on the client, you have to do a full recursive lookup. You've always been able to run your own DNS cache, if you want your host to operate independently of any upstream DNS server. But at that point, you're simply running your own DNS server.
Show threadjcalvinowensFeb 28
It's not necessarily equivalent to a recursive lookup, you can ask a cache for all the answers because you already know the root keys a priori. But yes, it does follow the entire chain of trust, that's the entire point of dnssec: if you don't do that the whole exercise is utterly pointless.
Show threadtptacekFeb 28

It's explicitly not the point of DNSSEC, which has for most of its entire existence been designed to be run as a server-to-server protocol, with stub resolvers trusting their upstream DNS servers.

I agree with you, though. It's utterly pointless.

Show threadjcalvinowensFeb 28
Not true, RFC4035 says all security aware resolvers SHOULD verify the signatures. It's far from pointless when actually implemented. Don't dismiss a whole protocol just because some historical implementations have been half assed.
Show threadtptacekFeb 28
The RFC uses "security-aware" to set them apart from ordinary resolvers, which are what every mainstream resolver uses.