mx4.itsec.md has no CNAME records.
Question and response
Question
dig mx4.itsec.md. NS
Answer
The response has no answer records.
Authority
itsec.md. 4087 SOA ns.itsec.md. dns-public.itsec.md. 2026021101 10800 3600 2419200 38400
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0