DNS CAA records...

Royce Williams royce at techsolvency.com
Wed Jan 18 01:54:28 UTC 2017

On Tue, Jan 17, 2017 at 3:04 PM, Eric Tykwinski <eric-list at truenet.com> wrote:
> So I’ve come across this on Qualys and just wondering if there’s any practical examples out there in the wild.
> I know some BIND guys are on here, so I’m sure I’m missing something from the RFCs.
> Just wanted to test this out on my play domains before putting it out in the wild...

As of 2016-12-31, here are CAA records for 143 domains:


That gist contains all CAA (or unparsed/raw type 257) records as seen
in the Rapid7 "DNS ANY" dataset [1] from 2016-12-31.

Interestingly, google.com as noted by Nolan side-thread isn't in this
dataset. Since "DNS ANY" is a superset of all DNS picked up by other
scans, it may be that Rapid7's scanning isn't incidentally catching
many CAA records. An explicit scan for CAA records (against, say, in
all domains seen in DNS ANY) would likely be interesting.

Also, I've requested that cPanel add CAA support to the DNS management
tools. If that would be of use to you, feel free to upvote the feature

Some good CAA refs are [3],[4],and [5].


1. https://scans.io/study/sonar.fdns
2. https://features.cpanel.net/topic/add-support-for-caa-dns-records-type-257
3. https://tools.ietf.org/html/rfc6844
4. https://sslmate.com/labs/caa/ (includes info on which CAs support
them; it's early)
5. https://blog.dnsimple.com/2017/01/introducing-caa-records/

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