What you'll learn in this article
- Unauthorized access to your work email can lead to data theft, fraud, or broader business compromise.
- Recognizing early warning signs such as password changes, suspicious messages, or unknown logins is critical.
- Immediate actions, like disconnecting from the network, changing credentials, and alerting IT, can help contain the threat.
- Recovery steps include checking account rules, scanning for malware, and notifying contacts to prevent further damage.
- Preventive measures such as multi-factor authentication, security awareness training, and advanced email protection from Mimecast reduce human risk and strengthen long-term resilience.
Finding out that your work email has been hacked can be stressful. Sensitive information, internal communication, and business relationships could all be at risk. Knowing what to do if your email is hacked can help you limit the damage, restore your account, and strengthen your security posture to prevent future attacks.
How to Know if Your Email Has Been Hacked
A compromised email account often shows clear warning signs. Recognizing them early helps prevent further damage.
Common indicators include:
- Unfamiliar emails appearing in your sent folder.
- Password or recovery settings changed without your knowledge.
- Login alerts from unknown locations or devices.
- Missing or deleted messages and altered email rules.
If you notice these warning signs, verify your account activity. Most email providers include a login history section that lists devices, IP addresses, and timestamps.
Use breach notification tools to see if your credentials were exposed, as well as use enterprise monitoring solutions such as Mimecast’s human risk management platform, which detects suspicious activity across email environments.
What to Do If Your Email Has Been Hacked
Once you confirm unauthorized access, it is essential to act quickly and methodically. Knowing what to do if your email is hacked can help mitigate further damage. Here’s what you need to do:
- Disconnect from the network. Temporarily disconnect the affected device from Wi-Fi or your company network to prevent further intrusion.
- Change your password securely. Use a trusted device to update your password. Choose a strong, unique combination of letters, numbers, and symbols.
- Log out of all active sessions. End all logged-in sessions from the account settings to remove the attacker’s access.
- Notify your IT or security team. Provide details about the incident so they can investigate logs and determine the extent of the compromise.
- Enable multi-factor authentication (MFA). After regaining control, activate MFA to add an extra layer of protection against future unauthorized access.
These actions form the first line of defense when responding to an email hack. Immediate containment helps prevent the attacker from spreading the breach to other systems.
How to Recover Access to a Compromised Account
If the attacker has locked you out of your account, use your email provider’s account recovery process. Most providers allow identity verification through a secondary email address or mobile number.
Once access is restored:
- Update recovery information. Replace old recovery emails or phone numbers that could be compromised.
- Check forwarding rules and filters. Hackers often create hidden filters to redirect messages to their inbox.
- Inspect drafts and sent folders. Look for unauthorized messages or phishing attempts that may have been sent under your name.
- Scan your device for malware. Use endpoint security tools to ensure that keyloggers or spyware are not still active.
If recovery fails, contact your provider’s support team or your organization’s administrator for direct assistance.
How to Protect Contacts and Stop Further Damage
After securing your account, focus on preventing the incident from spreading to others. Cybercriminals often use compromised accounts to target colleagues, clients, and vendors through phishing or fraudulent requests. Here’s what to do in case your account is compromised:
- Notify your contacts. Send a brief message informing them that your account was compromised and to disregard any unusual emails received recently.
- Clean up your mailbox. Delete unauthorized messages and remove any unknown filters or linked accounts.
- Run a system scan. Use trusted antivirus or endpoint protection to remove any remaining threats.
- Monitor connected applications. Review third-party integrations, especially those with access to sensitive data, and revoke unnecessary permissions.
Taking these measures limits reputational and financial damage and restores trust in your communications.
How to Prevent Future Email Hacks
Knowing what to do if your email is hacked is only part of the solution. Long-term protection requires consistent security practices and modern defense tools. Here are some things to keep in mind:
- Use strong, unique passwords. Change them periodically and avoid using the same password across multiple platforms.
- Turn on MFA for all accounts. Multi-factor authentication significantly reduces unauthorized access.
- Educate employees about phishing. Awareness training helps users identify suspicious links or requests before interacting with them.
- Leverage advanced email protection. Mimecast’s AI-powered email security solution detects and blocks malicious attachments, links, and behavioral anomalies across inbound, outbound, and internal communications.
Implementing layered defenses helps organizations reduce human risk, prevent account takeovers, and improve their overall security resilience.
Business Email Compromise (BEC): A Larger Threat
A single hacked inbox can lead to more serious incidents such as Business Email Compromise (BEC). These attacks manipulate trust by impersonating executives, vendors, or partners to request unauthorized payments or data transfers.
Unlike standard phishing, BEC attacks often use legitimate email threads and social engineering rather than malware. They begin with one compromised account and expand through targeted communication chains.
Preventing BEC requires visibility across all email traffic. Mimecast’s AI and behavioral analytics identify suspicious communication patterns and stop fraudulent messages before they reach employees. This comprehensive approach protects against both internal and external threats.
How Mimecast Helps Secure Your Email
Mimecast provides a unified solution for defending against the full spectrum of email threats. Its connected human risk platform combines advanced threat detection, data protection, and awareness training to create a stronger line of defense.
Key capabilities include:
- Real-time threat detection. AI-driven scanning prevents malicious links and attachments from reaching inboxes.
- Continuous monitoring. Automated alerts help security teams respond to suspicious behavior promptly.
- Security awareness training. Mimecast Engage improves user vigilance and reduces human error.
- Data protection and archiving. Ensures message integrity, compliance, and recoverability after incidents.
With more than 42,000 customers worldwide, Mimecast helps organizations work protected through greater visibility, control, and resilience.
Conclusion
Knowing what to do if your email is hacked can make a significant difference in minimizing damage. Responding quickly, practicing good credential hygiene, and using modern protection tools are key to preventing recurrence.
Protect your inbox and your organization with Mimecast. Learn more about how our solutions safeguard against the next email-based attack.