DMARC Digest

Everything you need to know about DMARC fundamentals.

What is DMARC?

Domain-based Message Authentication, Reporting and Conformance, commonly known as DMARC, is an email authentication, policy, and reporting protocol. It is designed to give email domain owners the ability to protect their domain from unauthorized use, commonly known as email spoofing. The purpose and primary outcome of implementing DMARC is to protect a domain from being used in business email compromise attacks, phishing email, email scams and other cyber threat activities.

How DMARC works?

Once the DMARC DNS entry is published, any receiving email server can authenticate the incoming email based on the instructions published by the domain owner within the DNS entry. If the email passes the authentication, it will be delivered and can be trusted. If the email fails the check, depending on the policy applied within the DMARC record the email could be delivered (p=none), quarantined (p=quarantine) or rejected (p=reject).

When the DMARC policy is enforced to p=reject, organizations are protected against:

Phishing on customers of the organisation

Brand abuse & scams

Malware and Ransomware attacks

Employees from spear phishing and CEO fraud to happen

DMARC safeguards your email

Preventing email fraud saves time and money. DMARC blocks unauthorized email senders by filtering unwanted emails before they reach recipients. It also improves business email deliverability by making it easier for mail providers to discern between phishing attempts and legitimate marketing activities.

Aligning with DMARC

DMARC extends two existing email authentication mechanisms, Sender Policy Framework (SPF) and DomainKeys Identified Mail (DKIM), allowing the administrative domain owner to publish a policy in their DNS records and specify which mechanism (DKIM, SPF or both) is employed when sending email from that domain. SPF and DKIM are mostly familiar technologies, but neither of them can possibly protect from spoofing or other misuse of your domain. The main control to observe and restrict email domain usage is DMARC. Therefore, DMARC is a must for every domain owner.