• Posted by: Eng. Donya Bino
• October 23, 2025

Protecting Email: Practical Steps to Stop Phishing and Data Loss

Email is the single most abused tool in cybercrime. It carries everything: invoices, contracts, passwords, links, and sometimes the keys to your business. That makes it a favorite target for scammers, phishers, and attackers who want access to systems or sensitive data.

Everyday risks to watch for

1. Phishing messages pretending to be banks, coworkers, or vendors.
2. Spear phishing that targets specific people (CEO, finance) with convincing context.
3. Malicious attachments and links that install malware or steal credentials.
4. Account takeover when passwords are weak or reused.
5. Data leakage when sensitive info is sent to the wrong address or forwarded carelessly.

Practical protections everyone should use

1. Use strong, unique passwords and MFA

1. Long passphrases beat short passwords. Use a password manager.
2. Always enable multi-factor authentication for email accounts. MFA blocks most automated takeover attempts.

2. Enable DMARC, DKIM, and SPF for your domains

1. These are DNS records that reduce spoofing and make it harder for attackers to send email as your domain.
2. Set them up, start in “monitor” mode, then move to “reject” when confident.

3. Train people to spot phishing

1. Teach the simple checks: sender address vs display name, unexpected requests for money or credentials, misspellings, odd urgency.
2. Run simulated phishing exercises and follow up with coaching, not shaming.

4. Be careful with attachments and links

1. Don’t open attachments unless expected. If in doubt, verify by a separate channel (call the sender).
2. Hover over links to check the destination before clicking. Use link-expansion tools in mail clients where available.

5. Use email encryption for sensitive content

1. For personal or business secrets (contracts, PII), use end-to-end encryption or at least S/MIME/PGP where supported.
2. If encryption is too heavy for day-to-day, password protect documents and share the password separately.
6. Limit auto-forwarding and external sharing: Avoid rules that auto-forward mail to external addresses. Check forwarding rules periodically to catch abuse.
7. Lock down admin access and audit logs: Restrict who can change DNS/DMARC records and who manages email routing. Log all changes.
8. Scan attachments and use sandboxing: Use gateway scanners and sandboxing for attachments to block malicious files before they reach users.
9. Protect backup and archive mailboxes: Backups should be immutable where possible and stored off-network to survive ransomware attacks.

What to do if you suspect a phishing email

1. Stop. Do not click any links or open attachments.
2. Verify the sender by calling or messaging them outside of email.
3. Report the message to your security team or use your org’s “report phishing” button.
4. If you clicked a link or entered credentials, change passwords immediately and notify IT.
5. Preserve the email (don’t delete) and include headers if asked.

Real scenarios that show why this matters

1. A finance clerk gets a seemingly urgent invoice from a vendor and pays it. The vendor email was fake and the money is gone. Lesson: verify payment requests with a phone call to a known number.
2. An executive account gets phished using personal details pulled from social media. The attacker uses the mailbox to request payroll changes. Lesson: limit public exposure and require step-up MFA for sensitive operations.
3. A salesperson forwards a contract containing client PII to a personal Gmail address and that account is later compromised. Lesson: block external forwarding and treat PII as sensitive by default.

Small org checklist you can adopt today

1. Enforce MFA for all mailboxes.
2. Set up SPF/DKIM and a DMARC policy (start with monitor).
3. Enable “report phishing” in your mail client and tell staff how to use it.
4. Block macros in Office attachments by default.
5. Require password managers and ban password reuse.
6. Schedule monthly phishing awareness micro-training, 15 minutes is fine.