What is Email & Messaging Security?
Email & Messaging Security is the set of tools and controls that protect email and messaging systems from threats such as phishing, business email compromise, malware, and domain spoofing. It covers inbound threat detection, outbound data protection, authentication enforcement, and encryption across email and collaboration channels.
What it does
Email & Messaging Security products sit between senders and recipients and inspect, filter, or block harmful content before it reaches users. Core functions include:
- Scanning inbound messages for phishing links, malicious attachments, and impersonation attempts
- Enforcing email authentication standards: SPF, DKIM, and DMARC
- Detecting business email compromise (BEC) by analyzing sender behavior and message context
- Blocking outbound messages that contain sensitive data (see Email DLP)
- Encrypting message content and attachments in transit and at rest (see Email Encryption)
- Archiving messages for compliance and legal hold (see Communications Archiving & Compliance)
- Applying Content Disarm & Reconstruction (CDR) to strip active content from attachments before delivery
Products in this category range from gateway filters that sit in front of a mail server to API-connected platforms that integrate directly with Microsoft 365 or Google Workspace after delivery.
Why teams buy it
Email remains the most common entry point for cyberattacks. A single successful phishing message can lead to credential theft, ransomware, or fraudulent wire transfers. Teams buy these tools to:
- Reduce the volume of malicious messages that reach employee inboxes
- Enforce DMARC so attackers cannot send email that appears to come from the organization's own domain
- Detect payment fraud and social engineering attempts that bypass simple spam filters
- Meet regulatory requirements for message retention and encryption
What to look for
- Integration method: gateway (MX record change) vs. API (post-delivery scanning). API-based tools can catch threats that arrive before a rule is written.