Credits: With additional data from Paul Vixie of Farsight Security,
the DNSSEC coverage continues to improve.
Summary: The DANE domain count is now 296,990.
The number DNSSEC domains in the survey stands at 8,069,614.
Thus DANE TLSA is deployed on 3.68% of domains with
DNSSEC.
As of today I count 296,990 domains with correct SMTP DANE TLSA
records at every primary MX host that accepts connections[1]. As
expected the bulk of the DANE domains are hosted by the DNS/email
hosting providers who've enabled DANE support in bulk for the
domains they host. It is starting to get crowded at the top of
the list, so I'm now listing the top 15 MX host providers by domain
count:
103783 transip.nl
96089 domeneshop.no
34141 active24.com
23491 udmedia.de
9646 bhosted.nl
2270 nederhost.nl
1940 provalue.nl (new this month)
1575 yourdomainprovider.net
1072 hi7.de
958 xcellerate.nl
874 surfmailfilter.nl
652 omc-mail.com
651 core-networks.de
588 interconnect.nl (new this month)
547 mailbox.org
The real numbers are surely larger, because I don't have access to
the full zone data for most ccTLDs, especially .no/.nl/.cz/.de.
Speaking of countries, the IPv4 GeoIP distribution of DANE-enabled
MX hosts shows the below top 10 countries (each unique IP address
is counted, so multi-homed MX hosts are perhaps somewhat
over-represented):
4080 TOTAL
1394 DE, Germany
900 US, United States
509 NL, Netherlands
338 FR, France
163 GB, United Kingdom
121 CZ, Czech Republic
80 CA, Canada
59 SE, Sweden
58 CH, Switzerland
57 SG, Singapore
IPv6 is still comparatively rare for MX hosts, and the top 10
countries by DANE MX host IPv6 GeoIP are (same top 6).
2043 TOTAL
768 DE, Germany
417 US, United States
282 NL, Netherlands
187 FR, France
89 GB, United Kingdom
68 CZ, Czech Republic
34 SE, Sweden
25 SG, Singapore
23 CH, Switzerland
14 SI, Slovenia
There are 3402 unique zones in which the underlying MX hosts are
found, this counts each of the above providers as just one zone,
so is a measure of the breadth of adoption in terms of servers
deployed.
The number of published MX host TLSA RRsets found is 4690. These
cover 5012 distinct MX hosts (some MX hosts share the same TLSA
records through CNAMEs).
The number of domains that at some point were listed in Gmail's
email transparency report is 157 (this is my ad-hoc criterion for
a domain being a large-enough actively used email domain). Of
these, 87 are in recent reports:
gmx.at fau.de deltion.nl
travelbirdbelgique.be freenet.de hierinloggen.nl
nic.br gmx.de interconnect.nl
registro.br jpberlin.de ouderportaal.nl
gmx.ch lrz.de overheid.nl
open.ch mail.de pathe.nl
anubisnetworks.com posteo.de politie.nl
gmx.com ruhr-uni-bochum.de truetickets.nl
mail.com tum.de uvt.nl
societe.com uni-erlangen.de xs4all.nl
solvinity.com unitybox.de domeneshop.no
t-2.com unitymedia.de webcruitermail.no
trashmail.com web.de aegee.orgxfinity.com egmontpublishing.dk debian.orgxfinityhomesecurity.com netic.dk freebsd.orgxfinitymobile.comtilburguniversity.edugentoo.org
active24.cz octopuce.fr ietf.org
clubcard.cz comcast.netisc.org
cuni.cz dd24.netnetbsd.org
cvc.cz dns-oarc.netopenssl.org
itesco.cz gmx.netsamba.org
klubpevnehozdravi.cz hr-manager.nettorproject.org
knizni-magazin.cz inexio.net asf.com.pt
nic.cz mpssec.net handelsbanken.se
optimail.cz t-2.net iis.se
smtp.cz xs4all.net minmyndighetspost.se
bayern.de bhosted.nl skatteverket.se
bund.de bit.nl t-2.si
elster.de boozyshop.nl govtrack.us
Of the ~297000 domains, 1142 have "partial" TLSA records, that
cover only a subset of the MX hosts. While this protects traffic
to some of the MX hosts, such domains are still vulnerable to the
usual active attacks via the remaining MX hosts.
The number of domains with incorrect TLSA records or failure to
advertise STARTTLS (even though TLSA records are published) stands
today at 266. Some of these have additional MX hosts that don't
have broken TLSA records, so mail can still arrive via the remaining
MX hosts. A partial list is available at:
https://github.com/danefail/list
To avoid getting listed, please make sure to monitor the validity
of your own TLSA records, and implement a reliable key rotation
procedure. See:
https://dane.sys4.de/common_mistakeshttp://imrryr.org/~viktor/ICANN61-viktor.pdfhttp://imrryr.org/~viktor/icann61-viktor.mp3http://tools.ietf.org/html/rfc7671#section-8.1http://tools.ietf.org/html/rfc7671#section-8.4
All the new blood in the survey has uncovered some previously unseen
DNSSEC denial of existence breakage. After eliminating parked
domains that do not accept email of any kind, the number of "real"
email domains with bad DNSSEC support stands at 678. The top 20
name server operators with problem domains are:
127 mijnhostingpartner.nl
79 webspacecontrol.com / dotroll.com
56 dotserv.com
42 metaregistrar.nl
40 is.nl
32 tiscomhosting.nl
29 active24.cz (some broken wildcard cnames)
27 tse.jus.br
26 sylconia.net
14 host-redirect.com
13 psb1.org
13 nazwa.pl (some broken wildcard NS RRs)
12 zeptor.nl
12 nrdns.nl
11 blauwblaatje.nl
8 dnscluster.nl
7 forpsi.net
6 pcextreme.nl
6 glbns.com
6 domdom.hu
If anyone has good contacts at one of these provides, please encourage
them to remediate not only the broken domains (I can send them a
list), but also the root cause that makes the breakage possible.
The domains all whose nameservers have broken denial of existsnce
that also appear in historical Google reports are:
trt1.jus.br
trtrj.jus.br
tre-ce.jus.br
tre-pe.jus.br
tre-rj.jus.br
tre-rs.jus.br
tre-sc.jus.br
tre-sp.jus.br
tse.jus.br
The last seven of these should be fixed shortly, the right parties
have been informed, and I expect will have resolved promptly.
--
Viktor.
[1] Some domains deliberately include MX hosts that are always
down, presumably as a hurdle to botnet SMTP code that gives up
where real MTAs might persist. I am not a fan of this type of
defence (it can also impose undue latency on legitimate email).
However, provided the dead hosts still have TLSA records, (which
don't need to match anything, just need to exist and be well-formed)
there's no loss of security.
