Why Email Still Matters
Introduction: Why Email Still Matters
For most small and mid-sized businesses, email is more than just communication. It drives cash flow and customer trust. Orders, invoices, supplier updates, and customer queries all flow through inboxes. That is why attackers target it. Most attacks do not need advanced hacking tools. They just need one person to be fooled by the wrong email.
At the heart of email security are three simple but critical ideas:
Authentication: Can I be confident that the person I am emailing, or who is emailing me, really is who they claim to be?
Confidentiality: Is this email private, like a sealed envelope, or exposed like a postcard?
Integrity: Can I be sure the invoice or attachment has not been tampered with?
Criminals exploit weaknesses in all three areas, and their favourite tactic is social engineering: manipulating trust, urgency or distraction to make people act without thinking.
Authentication: Can I Trust Who I Am Emailing?
One of the most common tricks is impersonation. Attackers set up fake email addresses or even fake websites that look almost identical to your real suppliers, staff or customers. They then send invoices, contracts or “urgent” requests that appear genuine.
Social engineering makes this work. Criminals rely on people assuming “this looks right” and acting quickly. A finance officer under pressure approves a payment, not noticing that the sender’s address has an extra letter or that the bank account details have changed.
Practical defences:
Turn on multi-factor authentication (MFA). Even if a password is stolen, MFA makes it useless to an attacker.
Configure your email system to verify senders automatically. This is done by using techniques such as SPF, DKIM and DMARC, which help stop criminals pretending to be you or a trusted partner.
Train staff to double-check unusual requests. A quick phone call to confirm is often enough to stop fraud.
Confidentiality: Is Your Email Private?
Sending sensitive data by email is like writing it on a postcard. Anyone who handles it along the way could read it. For routine business messages that is not a major risk. But when payroll details, contracts or account logins are sent by email, attackers get an opportunity to steal valuable information.
Social engineering makes this worse. Criminals rarely need to intercept messages. Instead they persuade people to hand over information. A convincing “HR request” or “IT support email” can trick staff into forwarding payslips or sharing login details, thinking they are helping a colleague.
Practical defences:
Avoid sending sensitive data like credit card numbers or passwords over email.
Use theencryption features already built into Microsoft 365 or Google Workspace when sending confidential information.
Make it clear that staff shouldnever email passwords. If someone asks, it is almost certainly a scam.
Integrity: Can You Trust the Message?
Some of the most damaging email attacks involve tampering, not just theft. It is like someone opening a letter on the way to you, changing the details, then resealing it so it looks untouched. Attackers do the same with invoices or documents, quietly swapping payment details so money flows to them instead of your suppliers.
Social engineering makes this more convincing. An attacker might follow up a doctored invoice with a phone call pretending to be the supplier, adding urgency to “get this sorted today.” Under pressure, even experienced staff can be tricked.
Practical defences:
Require a“call and confirm” policy for any change to payment details.
Usedual approval for financial transactions. One person enters, another approves.
Promote apause-and-check culture. Taking one extra minute to verify unusual requests prevents costly mistakes.
Practical, Low-Cost Defenses
Email is not just a technical channel. It is the most common way attackers blend technology with psychology to breach SMEs. Social engineering takes weaknesses in authentication, confidentiality and integrity, then turns them into business risks: stolen funds, exposed data and broken trust.
The good news is that building strong email security does not require a huge budget. Many protections are already included in Microsoft 365 or Google Workspace, and the rest comes down to clear processes and staff awareness.
Here are practical steps you can take today:
Turn on multi-factor authentication for all email accounts.
Configure your email system to verify senders automatically with SPF, DKIM and DMARC.
Use built-in encryption features when sending sensitive data.
Require a“call and confirm” process for payment changes.
Applied dual approval for financial transactions.
Build a pause-and-check culture by encouraging staff to question unusual requests and verify before acting.
With these measures in place, you reduce risk dramatically without needing a large IT budget. You can take back control over email security and protect the business from one of its biggest daily threats.
Conclusion: Protecting What Matters
Email is too important to leave exposed. It carries the conversations, approvals and transactions that keep your business running. Attackers know this, and they use social engineering to exploit weaknesses in authentication, confidentiality and integrity.
The good news is that SMEs do not need enterprise budgets to fight back. By combining simple technical settings with clear processes and staff awareness, you can cut out the majority of email risks before they turn into serious incidents.
At Heimdall Infosec, our focus is helping businesses protect what really matters: your people, your data and your reputation. Email is often the first line of attack, and it is the first place to build resilience.
If you would like to explore how your business can strengthen email security with practical, cost-effective steps, contact us for a no-obligation discussion.
