Email security risks to watch before you click or reply

A year’s worth of data from Microsoft’s email security systems offers a rare, large-scale look at how attackers are targeting inboxes today. While the benchmark was designed for enterprise administrators, many of the patterns apply just as much to personal Outlook.com or Microsoft 365 accounts. Understanding what the data shows—and what it doesn’t—can help you make smarter decisions about your own email defences.

What happened

Microsoft analysed telemetry from Defender for Office 365 over a twelve-month period. The company publishes its annual email security benchmark to show how threat detection performs and what kinds of attacks are most prevalent. According to the report, phishing remained the most common threat, followed by business email compromise (BEC) and credential harvesting campaigns. Attackers are not just sending generic spam; they are increasingly using contextual information, such as stolen email threads or legitimate-looking sender names, to trick recipients.

A separate Microsoft article from December 2025 highlighted a push for greater transparency in how email security is measured. The idea is that organisations—and by extension, users—need clearer visibility into which attacks are slipping through and why. The latest benchmark, published in June 2026, builds on that by showing year-over-year trends in detection accuracy and attacker behaviour.

Why it matters for personal accounts

It is easy to assume that sophisticated email attacks are reserved for executives or finance teams. But the same techniques—conversation hijacking, fake invoice requests, and password-reset phishing—are used against consumer accounts. Microsoft’s data indicates that attackers are less interested in broad spray-and-pray campaigns and more focused on targeted, socially engineered messages. That shift makes everyone a potential victim, regardless of account type.

The benchmark also shows that detection rates have improved, but not uniformly. Some attack patterns, like simple link-based phishing, are caught at high rates by Defender’s built-in filters. Others, especially those involving compromised real accounts or subtle sender impersonation, still require user vigilance. No filter is perfect, and the data makes that clear.

For someone using Outlook.com or a Microsoft 365 Family subscription, the practical implication is straightforward: you are a target, and the attackers are getting better at looking real.

What you can do to reduce your risk

You do not need to become a security administrator to benefit from these insights. A few concrete steps can meaningfully reduce your exposure.

  1. Enable multi-factor authentication (MFA). This is the single most effective protection against credential theft. If an attacker gets your password but cannot pass the second factor, the attack is stopped. Microsoft accounts support multiple MFA methods, including authenticator apps and security keys.

  2. Review your email forwarding rules. A common attacker move after compromising an account is to set up an inbox rule that forwards sensitive emails (like password resets or financial confirmations) to an external address. Check your own rules in Outlook settings periodically, especially if you notice odd email behaviour. Remove any rules you did not create.

  3. Scrutinise urgent requests for money or credentials. The benchmark confirms that BEC attacks often rely on a sense of urgency and impersonation of someone you trust. If an email asks you to act quickly—wire money, buy gift cards, or share a password—verify through a separate channel, such as a phone call or text.

  4. Turn on Microsoft Defender for personal use. If you have a Microsoft 365 subscription, you may already have access to Defender features like Safe Links and Safe Attachments. These scan links and attachments in real time, blocking malicious content before it reaches you. Check whether they are active in your security settings.

  5. Report suspicious emails. In Outlook, use the “Report phishing” button to alert Microsoft. This improves detection for everyone and can help protect contacts in your address book if your account is compromised.

  6. Be cautious with forwarded conversations. Attackers often insert themselves into existing email threads. If a reply seems slightly off—odd language, a different request—pause and verify before acting.

Sources

The insights in this article draw from Microsoft’s published findings:

These documents provide the enterprise context; the personal protection recommendations are derived from common security practices that align with the data’s conclusions. As with any security guidance, no single measure guarantees safety, but combining these steps will put you in a much stronger position than relying on filters alone.