What Is Email Spoofing and How to Prevent It

Imagine a customer receives an invoice that appears to come from your company - same domain, same branding - but it is a scam, and the bank details are the attacker's. That is email spoofing, and it damages the victim and your reputation at once. The good news: it is largely preventable. Here is how.

What is email spoofing?

Spoofing is when an attacker forges the "from" address of an email so it appears to come from someone else - often a trusted brand or colleague. Because email was not originally designed to verify senders, anyone can claim to send from your domain unless you take steps to stop them.

Why it is dangerous

Spoofing powers many of the costliest scams:

• Fake invoices sent to your customers using your name
• CEO fraud, where staff receive a "message from the boss" requesting an urgent payment
• Phishing that borrows your brand's trust to steal credentials

Every spoofed message that goes out under your name erodes trust in your business - even though you never sent it.

How to prevent spoofing

Spoofing is stopped by authenticating your domain with three DNS records that let receiving servers verify your mail:

• SPF lists the servers allowed to send for your domain
• DKIM adds a tamper-proof signature to your messages
• DMARC tells receivers what to do when a message fails SPF or DKIM - and can instruct them to reject spoofed mail outright

Together they make it very hard for anyone to send convincing mail as your domain. We explain each in SPF, DKIM and DMARC explained, and DMARC's reporting in DMARC reports explained.

Set DMARC to enforce

Many businesses set up SPF and DKIM but leave DMARC in "monitor" mode, which does not block anything. To actually stop spoofing, you progress DMARC from p=none (monitor) to p=quarantine and finally p=reject once you confirm your legitimate mail passes. Then spoofed messages are refused.

Protect inbound too

Authentication stops others spoofing your domain. Strong inbound filtering protects your team from spoofed mail impersonating others - see how to stop spam and phishing.

We handle it for you

DigiCloudMail helps you configure SPF, DKIM and DMARC correctly and move DMARC to enforcement safely - so scammers cannot hide behind your brand.

Want to stop anyone spoofing your domain? Get in touch and we will lock it down.