Email is a critical component of modern communication, and it has become a primary target for cyber attackers. They often spoof email addresses to trick people into providing sensitive information or downloading malware. To prevent this, you need to implement three email security controls on your domain – SPF, DKIM, and DMARC.
What are SPF, DKIM, and DMARC?
SPF (Sender Policy Framework) is a type of email authentication that specifies which IP addresses are authorized to send emails on behalf of your domain. It works by publishing a DNS record with a list of authorized senders. When an email server receives an email from your domain, it checks the SPF record to verify if the sender is authorized to send emails on your behalf.
DKIM (DomainKeys Identified Mail) is another email authentication method that uses digital signatures to verify the authenticity of an email. It works by adding a digital signature to the email header, which is verified by the recipient’s email server using a public key published in your domain’s DNS records.
DMARC (Domain-based Message Authentication, Reporting, and Conformance) is a policy that combines SPF and DKIM to ensure the authenticity of an email. It checks if the email passes SPF and DKIM authentication, and if it doesn’t, it can either quarantine or reject the email.
Why do you need SPF, DKIM, and DMARC?
Attackers often spoof email addresses to make it look like the email is coming from a legitimate source. This technique is commonly used in phishing emails, where attackers trick people into revealing sensitive information, such as login credentials or credit card numbers. By implementing SPF, DKIM, and DMARC, you can prevent attackers from spoofing your email address and sending phishing emails to your customers.
How to implement SPF, DKIM, and DMARC?
To implement SPF, you need to add a TXT record to your DNS settings with a specific configuration that includes authorized senders for your domain. You can find detailed instructions on how to set up SPF for popular email providers like Microsoft 365, Google Workspace, and Yahoo on their respective websites.
To implement DKIM, you need to generate a public-private key pair and publish the public key in your domain’s DNS records. You also need to configure your email server to sign outgoing emails with the private key. Again, you can find detailed instructions on how to set up DKIM for popular email providers on their respective websites.
To implement DMARC, you need to add a DMARC record to your DNS settings with a policy that specifies what to do with emails that fail SPF and/or DKIM authentication. You can choose to either quarantine or reject such emails. Again, you can find detailed instructions on how to set up DMARC for popular email providers on their respective websites.
Conclusion
Email security is critical, and by implementing SPF, DKIM, and DMARC, you can improve your email security and prevent attackers from spoofing your email address. Implementing these controls may seem daunting, but popular email providers have made it easier by providing step-by-step instructions on their websites. By taking these simple steps, you can protect yourself and your customers from phishing emails and other email-based attacks.