It’s no exaggeration — over 90% of successful cyberattacks start with an email. Whether you work in a bustling office, from your home, or on the go with your smartphone, email remains the backbone of communication. Unfortunately, it’s also the number one entry point for cybercriminals.
From fake invoices to cleverly disguised malware, attackers have mastered the art of making dangerous emails look legitimate. Click once without thinking, and you could expose sensitive company data, compromise customer records, or even shut down an entire network.
The good news? With the right awareness, you can spot most malicious emails before they cause any damage. In this guide, we’ll cover the most common email threats, the top warning signs to watch for, and the simple verification steps that can keep you and your company safe.
Why Email Safety Matters
Email is fast, convenient, and reliable, which is exactly why cybercriminals love it. According to the 2024 Verizon Data Breach Investigations Report, email remains the top vector for phishing and malware delivery. Attackers know that a well-crafted message can bypass even the most advanced technical defenses if it tricks a human into clicking.
The consequences can be severe:
- Financial loss — Fake payment requests can lead to direct theft.
- Data breaches — A single click can expose confidential business or customer data.
- Reputation damage — Clients may lose trust if they discover a breach originated with an employee.
The truth is, cybersecurity isn’t just an IT department responsibility anymore. Every employee is now part of the frontline defense. Knowing how to spot a suspicious email is a skill every worker needs.
Common Email Threat Types
1. Phishing Emails
Phishing is when attackers pretend to be a trusted source, like your bank, HR department, or a known vendor — to trick you into revealing sensitive information.
Example: You receive an “urgent” message from your payroll provider saying your account details need verification immediately. The link takes you to a fake login page that steals your credentials.
Signs of phishing emails:
- Generic greetings (“Dear User”) instead of your name.
- Spelling or grammar errors.
- A sense of urgency or fear.
- Links that don’t match the displayed URL.
2. Email Spoofing
Spoofing is when the sender’s address is forged to look like it came from a legitimate source.
Example: A message appears to be from your CEO asking for an immediate wire transfer — but the email domain has an extra letter, like ceo@companny.com instead of company.com.
How to spot spoofing:
- Check the full sender email address, not just the display name.
- Inspect email headers for discrepancies.
- Confirm requests via a separate communication channel before acting.
3. Malicious Attachments
Some emails carry infected files designed to install malware when opened. These could include ransomware, spyware, or credential-stealing programs.
Example: An “invoice” attachment labeled Invoice.pdf.exe installs a Trojan when clicked.
Common malicious file disguises:
- PDFs with embedded scripts.
- Word/Excel files with macros.
- Compressed ZIP or RAR files that contain hidden executables.
Dangerous File Types to Watch Out For
Certain file types are so often abused that you should treat them with extreme caution:
- Executable files (.exe, .bat, .cmd): Can run malicious programs instantly.
- Macro-enabled Office files (.docm, .xlsm): Can run hidden scripts.
- Compressed archives (.zip, .rar): Can hide malware from email filters.
- PDF files with scripts: May exploit vulnerabilities in PDF readers.
Golden rule: If you weren’t expecting the file, don’t open it without verifying the sender.
Top Red Flags of a Malicious Email
- Suspicious Sender Address: Look closely — attackers often use slight misspellings or different domain endings.
- Urgent or Threatening Language: Cybercriminals rely on panic to get you to act without thinking.
- Unexpected Attachments or Links: Even if it’s from someone you know, their account could be compromised.
- Poor Grammar or Strange Formatting: Many scams originate overseas and have awkward phrasing.
- Mismatched URLs: Hover over links to see the real destination before clicking.
How to Verify a Suspicious Email
- Hover Before Clicking: Place your cursor over links to preview the destination without clicking.
- Check the Full Email Address: A display name can be faked — the real danger is in the domain.
- Compare Writing Style: Is the tone or formatting unusual for that sender?
- Confirm via a Separate Channel: Call or text the person to verify they sent the message.
- Send to IT/Security for Review: Most companies have procedures for reporting suspicious emails.
Safe Handling Practices for Employees
- Keep your email software and devices updated.
- Disable automatic image downloads to prevent tracking.
- Use antivirus software with email scanning features.
- Never reply to suspicious emails — it confirms your address is active.
- Report suspicious messages immediately instead of ignoring them.
How Training Reduces Email Risks
No matter how good your instincts are, attackers are constantly evolving their tactics. That’s why ongoing training is essential.
Tiraza’s Email Safety & Spotting Malicious Attachments course offers:
- Real-world phishing and spoofing examples.
- Step-by-step guidance for verifying suspicious messages.
- Hands-on practice with identifying dangerous file types.
Training ensures you’re not just reacting — you’re staying ahead.
Conclusion
Dangerous emails are everywhere, from cleverly disguised phishing attempts to malware-laden attachments. But by knowing the signs, verifying before you click, and practicing safe email habits, you can protect yourself and your organization.
Remember: email security is a shared responsibility. Stay cautious, stay informed, and make email safety a daily habit.
Ready to sharpen your skills?
Signup for Tiraza’s Email Safety & Spotting Malicious Attachments Course today and learn how to spot threats before they reach your inbox.