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 This message originated outside of NETSCOUT. Do not click links or open attachments unless you recognize the sender and know the content is safe. 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 ________________________________ This email has been scanned for email related threats and delivered safely by Mimecast. For more information please visit http://www.mimecast.com<https://urldefense.proofpoint.com/v2/url?u=http-3A__www.mimecast.com&d=DwMFaQ&c=Hlvprqonr5LuCN9TN65xNw&r=VfFQaWKwN0L3efDXtkWoSUKlJtu8LJ9Ke5bevkfX6C0&m=q6vn3t-QWxYOtFEQ5UhCttLDcerYncizhmA0BXauzSg&s=0udD7os_Gb1eyxuW47ezLZB2f-gk_Ipxso3m4n80kqg&e=> ________________________________