Reverse DNS Checks
Reverse DNS is a PTR record that points back to the domain name. RFC 1912 published by the IETF, recommends that every domain pointing to an IP address should have a PTR record pointing back to the domain name. This is especially important for e-mail servers, where a reverse domain DNS check is done in order to prevent unauthorized IP addresses from sending emails on behalf of the domain name.
If you fail to have a reverse DNS check on Onlayer, this means that your email server IP address has no reverse DNS entry or it doesn’t point to the original email server, and so you might be vulnerable to attackers using your domain name to send emails.
Solution
Please check your servers IP and reverse DNS name and make sure that the mail server is pointing to the server you know.
LEGAL
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