This is was my thought as well. People always get up in arms about how it's "Public DNS!" but it's really not. It's just well known and used because it's easy to remember. - Mike Bolitho On Tue, Nov 19, 2019 at 9:28 AM Ryan, Spencer <spencer.ryan@netscout.com> wrote:
Are you a CL/L3 customer? Those resolvers have only ever been for “customers” even though they would resolve for anyone. They started injecting NXDOMAIN redirects a while ago for non-customers.
*From:* NANOG <nanog-bounces@nanog.org> *On Behalf Of *Marshall, Quincy *Sent:* Monday, November 18, 2019 12:45 PM *Subject:* Level(3) DNS Spoofing All Domains
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This is mostly informational and may have already hit this group. My google-foo failed me if so.
I discovered that the CenturyLink/Level(3) public DNS (4.2.2.2, etc) are spoofing all domains. If the hostname begins with a “w” and does not exist in the authoritative zone these hosts will return two Akamai hosts.
[root@localhost ~]# dig +short w3.dummydomaindoesntexist.gov @4.2.2.2
23.202.231.167
23.217.138.108
[root@localhost ~]# dig +short w3.dummydomaindoesntexist.net @4.2.2.2
23.202.231.167
23.217.138.108
[root@localhost ~]# dig +short w3.dummydomaindoesntexist.com @4.2.2.2
23.202.231.167
23.217.138.108
[root@localhost ~]# dig +short w3.dummydomaindoesntexist.org @4.2.2.2
23.202.231.167
23.217.138.108
My apologies if this is old news.
*Lawrence Q. Marshall*
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