The Layers of an Email Security Tech Stack (Part 2 of 3)

In today’s increasingly connected world, cybersecurity is a critical concern, especially as email remains one of the most targeted entry points for cyberattacks. One of the key components in a comprehensive email security strategy is email encryption technology. A Secure Email Gateway (SEG) plays a foundational role in ensuring that email traffic remains secure and free from threats such as spam, phishing, and malware. However, while SEGs are essential, they cannot provide the complete protection needed in a multi-layered email security approach.

In this blog post, we continue to explore the critical layers of an email security stack, focusing on how SEGs fit into the larger picture. While SEGs serve a crucial function, they cannot cover all aspects of email security, especially when dealing with advanced threats. Here, we break down the role of SEGs in email security and examine areas where additional layers are necessary.

What is a Secure Email Gateway (SEG)?

A Secure Email Gateway (SEG) serves as an essential first line of defense in protecting your inboxes from unwanted emails, including spam, phishing, and malware. SEGs help ensure that good emails are delivered to your users, while unwanted threats are filtered out before they can reach the mail server. However, SEGs only cover certain aspects of email security, and additional layers of protection are required for a complete strategy.

SEG Coverage of Email Security Layers:

1. Spam Filters: Yes, this is a primary function of SEGs.
2. Phishing Protection: Detects phishing emails through various techniques.
3. Malware and Ransomware Protection: Provides protection against malware by scanning and sandboxing incoming emails.
4. Data Loss Prevention (DLP): Often included in SEGs but capabilities can vary.
5. Encryption: Yes, SEGs typically support TLS encryption and may offer additional encryption options.
6. Email Authentication: Supports SPF, DKIM, and DMARC validation for email authentication.
7. Threat Intelligence Sharing: Provides limited integration with external threat intelligence feeds for enhanced protection.
8. User Training and Awareness: Typically outside the scope of SEGs and requires a separate initiative.
9. Archiving and Backup: Not usually included in SEGs; these functions are generally handled by other solutions.
10. Incident Response and Reporting: Provides partial automation, but comprehensive incident response requires additional tools.

Popular SEGs in the Market

There are many popular SEGs in the market, each offering a variety of features designed to protect against email-based threats. Here are a few examples:

• Proofpoint Email Protection: Provides comprehensive defense mechanisms against a wide range of email threats. It includes data loss prevention, email encryption, and advanced machine learning for threat detection.
• Mimecast Email Security Cloud Gateway: Known for its strong defense against both known and emerging email threats, using behavioral analysis and machine learning techniques.
• Barracuda Email Security Gateway: Offers protection against spam, phishing, viruses, and spyware, with inbound and outbound filtering capabilities and data loss prevention features.

What Doesn’t SEG Cover for Complete Email Security?

While SEGs play a crucial role in protecting against a variety of email threats, they have some limitations:

1. Advanced Threats Beyond Initial Delivery: SEGs are primarily focused on filtering threats at the point of delivery. They may not be as effective against advanced threats that evolve after the initial delivery.
2. Internal Email Threats: SEGs usually focus on external threats, which means they may not adequately address internal threats such as phishing attacks from compromised internal accounts.
3. Encrypted Email Threats: SEGs may struggle to inspect encrypted emails, leaving them blind to threats in encrypted communication.
4. Fileless Attacks and URL-based Threats: SEGs can be ineffective against fileless attacks and malicious URLs, which do not involve traditional malware.
5. Post-Delivery Threat Discovery: SEGs typically do not remove or quarantine emails that are discovered to be malicious after being delivered.
6. User Behavior and Targeted Phishing Attacks: SEGs cannot prevent phishing attacks that rely on social engineering techniques, as these do not always involve detectable malware signatures.
7. Comprehensive Data Loss Prevention (DLP): While SEGs provide some DLP capabilities, they may lack the granularity needed for more comprehensive protection.

Addressing These Shortcomings

To overcome the limitations of SEGs, organizations should implement additional layers of email security:

• Advanced Threat Protection (ATP): ATP solutions use behavioral analysis and machine learning to detect advanced threats that bypass traditional filters.
• Internal Email Monitoring: Internal email monitoring tools help detect threats originating from compromised internal accounts.
• Endpoint Detection and Response (EDR): EDR solutions identify and mitigate threats at the device level.
• Security Awareness Training: Educate users to recognize and respond to phishing and other social engineering attacks.
• SIEM Integration: Integrating SEGs with SIEM systems enhances visibility and improves incident response.

While SEGs are critical for email security, a multi-layered approach that includes additional tools and practices will provide more comprehensive protection against all types of email threats.

For further details, check out our [guide to email security](https://abusix.com/products/email-security) and our [email encryption technology](https://abusix.com/blog/email-encryption) overview.