Shielding Your Inbox: Configuring AWS WorkMail Security Gateways for Authenticated Emails

 

The ever-growing threat of phishing and email spoofing necessitates robust security measures for your business email. AWS WorkMail offers a secure email service, but additional configuration can further enhance your inbox protection. This article explores how to configure the AWS WorkMail security gateway to allow only authenticated emails to land in your inbox.

Understanding Email Authentication Protocols:

Email authentication protocols verify the sender's legitimacy, reducing the risk of receiving emails from spoofed addresses. Here are two key protocols:

• Sender Policy Framework (SPF): An SPF record published in the sender's DNS zone specifies authorized email servers for that domain. Receiving servers can check the SPF record to verify if the sender's IP address is legitimate.
• DomainKeys Identified Mail (DKIM): A cryptographic authentication method where the sender signs the email with a private key. The receiving server verifies the signature using the sender's public key published in a DNS record (DKIM record).

Configuring the WorkMail Security Gateway:

By default, WorkMail performs some level of spam and phishing filtering. However, to enforce authenticated emails only, additional configuration is required. Here's a breakdown of the steps:

1. Enable WorkMail Message Filtering: Navigate to the WorkMail console and select your organization. Go to "Inbound Mail Flow" and choose "Edit." Under "Message Filtering," select "Reject messages that fail authentication checks." This ensures emails that fail SPF or DKIM checks are rejected.
2. Verifying Sender Domain Configuration: For domains you regularly receive emails from, ensure they have SPF and DKIM records published in their DNS zone. You can use online tools to verify these records.
3. Whitelisting Trusted Senders (Optional): If specific senders don't utilize SPF or DKIM (e.g., internal mail server), you can whitelist their email addresses in the WorkMail console under "Inbound Mail Flow" -> "Edit" -> "Whitelisted Senders." This allows emails from these addresses to bypass authentication checks. Use this option cautiously.

Additional Security Measures:

• User Education: Educate your users about phishing scams and how to identify suspicious emails.
• Multi-Factor Authentication (MFA): Enable MFA for WorkMail accounts to add an extra layer of security beyond passwords.
• DMARC (Optional): DMARC (Domain-based Message Authentication, Reporting & Conformance) is a more comprehensive email authentication protocol that builds upon SPF and DKIM. It allows reporting on authentication failures, providing valuable insights into potential email spoofing attempts.

Benefits of Enforcing Authenticated Emails:

• Reduced Phishing Risk: By rejecting emails that fail authentication checks, you significantly reduce the risk of phishing attacks that attempt to impersonate legitimate senders.
• Increased Inbox Security: Only emails from authorized sources will reach your inbox, minimizing exposure to malicious content.
• Improved User Confidence: Knowing your email system prioritizes secure communication builds trust and confidence among users.

Considerations:

• Impact on Legitimate Emails: Enforcing strict authentication might initially block some legitimate emails from senders without proper SPF/DKIM configuration. Work with senders to ensure proper authentication protocols are in place.
• Monitoring and Adjustments: Monitor email delivery logs after implementing these changes. If legitimate emails are blocked, adjust whitelisting or consider a temporary relaxation of the filtering rules while working with senders to implement proper authentication.

Conclusion:

Configuring the AWS WorkMail security gateway to allow only authenticated emails adds a powerful layer of security to your organization's email infrastructure. By combining email authentication protocols with user education and other security measures, you can create a more secure and reliable email environment for your team. Remember, a layered approach to security is vital in today's ever-evolving threat landscape.