nanog mailing list archives

RE: A Deep Dive on the Recent Widespread DNS Hijacking


From: "Keith Medcalf" <kmedcalf () dessus com>
Date: Sun, 24 Feb 2019 18:51:51 -0700


Obviously none of y'all read the report.  Here is the relevant quote:

""""
DNSSEC protects applications from using forged or manipulated DNS data, by requiring that all DNS queries for a given 
domain or set of domains be digitally signed. In DNSSEC, if a name server determines that the address record for a 
given domain has not been modified in transit, it resolves the domain and lets the user visit the site. If, however, 
that record has been modified in some way or doesn’t match the domain requested, the name server blocks the user from 
reaching the fraudulent address.

While DNSSEC can be an effective tool for mitigating attacks such as those launched by DNSpionage, only about 20 
percent of the world’s major networks and Web sites have enabled it, according to measurements gathered by APNIC, the 
regional Internet address registry for the Asia-Pacific region.

Jogbäck said Netnod’s infrastructure suffered three separate attacks from the DNSpionage attackers. The first two 
occurred in a two-week window between Dec. 14, 2018 and Jan. 2, 2019, and targeted company servers that were not 
protected by DNSSEC.

However, he said the third attack between Dec. 29 and Jan. 2 targeted Netnod infrastructure that was protected by 
DNSSEC and serving its own internal email network. Yet, because the attackers already had access to its registrar’s 
systems, they were able to briefly disable that safeguard — or at least long enough to obtain SSL certificates for two 
of Netnod’s email servers.

Jogbäck told KrebsOnSecurity that once the attackers had those certificates, they re-enabled DNSSEC for the company’s 
targeted servers while apparently preparing to launch the second stage of the attack — diverting traffic flowing 
through its mail servers to machines the attackers controlled. But Jogbäck said that for whatever reason, the attackers 
neglected to use their unauthorized access to its registrar to disable DNSSEC before later attempting to siphon 
Internet traffic.

“Luckily for us, they forgot to remove that when they launched their man-in-the-middle attack,” he said. “If they had 
been more skilled they would have removed DNSSEC on the domain, which they could have done.”
"""

If you manage to get access to the change the dns delegation at the parent you can also turn DNSSEC off.  Clearly the 
scripties managed to do this once but "forgot" to do it the second time around ... That they also "forgot" to disable 
DNSSEC on PCH is not particularly relevant.  It only goes to prove my point that DNSSEC is irrelevant and only gives a 
false sense of security (for this particular attack vector).  I suppose you could have really long timeouts on your DS 
records, but that would merely "complicate" matters for the scripties and would not be protective ...


---
The fact that there's a Highway to Hell but only a Stairway to Heaven says a lot about anticipated traffic volume.

-----Original Message-----
From: Montgomery, Douglas (Fed) [mailto:dougm () nist gov]
Sent: Sunday, 24 February, 2019 15:38
To: nanog () nanog org
Cc: kmedcalf () dessus com
Subject: RE: A Deep Dive on the Recent Widespread DNS Hijacking

You might have missed reading the very article you cite.

"Woodcock said PCH’s reliance on DNSSEC almost completely blocked
that attack, but that it managed to snare email credentials for two
employees who were traveling at the time.
....
Aside from that, DNSSEC saved us from being really, thoroughly
owned.”



Or maybe ACME .. https://tools.ietf.org/html/draft-ietf-acme-acme-
12#section-11.2

"It is therefore RECOMMENDED that ACME-based CAs make all DNS queries
via DNSSEC-validating stub or recursive resolvers.  This provides
additional protection to domains which choose to make use of DNSSEC.”

I am not sure how many of the domains listed as being hijacked are
DNSSEC signed, but it seems if they were, and had a reasonable long
TTL on a DS record at their parent, many if not most of these could
have been prevented/detected.

ICANN seems to think that is the case: ICANN Calls for Full DNSSEC
Deployment
https://www.icann.org/news/announcement-2019-02-22-en

Of course, DNSSEC is often blamed for not protecting those who did
not deploy/use it.  Not sure what can be said about that line of
reasoning.

Dougm
--
Doug Montgomery, Manager Internet  & Scalable Systems Research @ NIST



============
   Date: Sat, 23 Feb 2019 12:13:41 -0700
   From: "Keith Medcalf" <kmedcalf () dessus com>
   To: "nanog () nanog org" <nanog () nanog org>
   Subject: RE: A Deep Dive on the Recent Widespread DNS Hijacking
      Attacks
   Message-ID: <6e31d305aee69c4d85116e6a81d0c91d () mail dessus com>
   Content-Type: text/plain; charset="us-ascii"

   On Saturday, 23 February, 2019 10:03, Stephane Bortzmeyer wrote:

   >Very good article, very detailed, with a lot of technical
precisions,
   >about the recent domain name hijackings (not using the DNS, just
good
   >old hijackings at registrar or hoster).

   >https://krebsonsecurity.com/2019/02/a-deep-dive-on-the-recent-
widespread-dns-hijacking-attacks/

   So in other words this was just an old school script kiddie
taking advantage of DNS registrars, the only difference being this
was a whole whack of script kiddies acting in concert directed by a
not-quite-so-stupid script kiddie, with some "modernz" thrown in for
good measure.  (Sounds like an NSA operation to me -- and the targets
perfectly match those that the NSA would choose -- plus some good old
misdirection just for the jollies of it)

   The second takeaway being that DNSSEC is useless in preventing
such an occurrence because the script kiddies can merely turn it off
at the same time as they redirect DNS.  However, having DNSSEC can
protect you from incompetent script-kiddies.  It can also give you a
false sense of security.

   Did I miss anything?

   ---
   The fact that there's a Highway to Hell but only a Stairway to
Heaven says a lot about anticipated traffic volume.







Current thread: