Trustwave Launches MailMarshal Integrated Cloud to Enhance Email Security for Microsoft 365 Environments

• Discover how Trustwave MailMarshal Integrated Cloud enhances your Microsoft 365 environment security.
• Learn how Trustwave MailMarshal Integrated Cloud's API-seamlessly integrates with M365.
• Trustwave MailMarshal secure email service now offers an integrated cloud solution to bolster your defenses against phishing, malware, and BEC attacks.

Trustwave has introduced MailMarshal Integrated Cloud. A new email security offering which is designed to deliver advanced, layered protection for organizations using Microsoft 365.

MailMarshal Integrated Cloud is a cloud-native solution that provides a seamless, API-led security layer that enhances resilience against sophisticated email threats, making it even easier for organizations operating in a Microsoft 365 environment to create a layered defense.

A New Approach to Layered Email Security

MailMarshal Integrated Cloud is a new, two-tiered secure email service offering designed to take an organization’s protection measures to the next level by providing a non-disruptive, highly effective layered security approach that blocks the latest sophisticated threats before they reach your employees, reducing the risk of costly data breaches and financial loss.

Built specifically for Microsoft 365 environments, the solution leverages API integration with M365 to deliver fast onboarding, enhanced threat detection, and increased redundancy—without requiring any change to an organization's MX records.

This cloud-native architecture ensures comprehensive coverage by scanning both inbound, outbound, and internal messages. The email can be seen in the image below, but here is an illustration of what happens with Trustwave MailMarshal Integrated Cloud for an inbound email.

1. Microsoft sends their “screened” emails to MailMarshal, where it is scanned again, removing any additional dangerous emails.
2. MailMarshal then sends the email back to Microsoft, which delivers the email to the recipient.
3. Microsoft sends their “good” emails to MailMarshal, where it is scanned again, removing any dangerous emails that Microsoft missed
4. MailMarshal then sends it back to Microsoft, who delivers the mail to the recipient
5. The entire process takes less than a second.

Figure 1. Illustration of Trustwave's MailMarshal Integrated Cloud for an inbound email process.

The Danger is Real

The need for ever stronger email security services has never been greater. The Federal Bureau of Investigation’s (FBI) Internet Crime Complaint Center noted in its latest report that the vast majority of crimes reported in 2024 were related to phishing.

These numbered 193,407, or more than double the next most numerous, extortion, and three times as many as personal data breaches at 64,882. Business email compromise (BEC) complaints numbered 21,442, which were about on par with the previous year.

These phishing scams resulted in an excess of $70 million in losses. However, BEC losses were listed at $2.7 billion, down from $2.9 billion in 2023.

API-Driven, Non-Disruptive Deployment

With API-led integration, MailMarshal Integrated Cloud can be deployed in minutes—eliminating operational friction and minimizing security gaps. Unlike traditional secure email gateway models, this approach allows Microsoft 365 to handle final message delivery, preserving uptime. This built-in resilience ensures emails continue to flow without interruption.

New API-led service enabling new capabilities

Trustwave MailMarshal Integrated Cloud also introduces powerful new capabilities through its API-led architecture—most notably, visibility into internal email traffic, a critical advancement for identifying and stopping insider threats, compromised accounts, and lateral phishing attacks. This internal inspection ensures that malicious messages circulating within an organization are detected and blocked before they can escalate into a data breach or widespread compromise. The API-based design is a future-ready platform that establishes a foundation for continuous innovation, enabling Trustwave to rapidly deliver new security features, expand integrations, and respond quickly to emerging threats—without requiring complex infrastructure changes or disruptions to mail flow.

Two Flexible Tiers: Essentials and Advanced

Trustwave offers MailMarshal Integrated Cloud in two service levels to meet varying security needs:

• Essentials – Delivers core MailMarshal protection, including advanced spam filtering, malware detection, and phishing defense.
• Advanced – Adds sandboxing, image-based threat detection, and QR codes analysis to defend against modern, stealthy attack vectors. These capabilities address emerging threats where attackers embed malware in images or use QR codes to lure users to malicious websites - tactics increasingly common in phishing and BEC campaigns.

Why MailMarshal

With more than 25 years of proven leadership, MailMarshal remains the industry’s most trusted and flexible email security solution. Key benefits include:

• 99.99% phishing and malware detection rate
• Zero reported client ransomware infections in over two decades
• <0.001% false positives, minimizing disruption to business operations
• Five proprietary AI/ML engines for advanced threat detection
• Ongoing threat research from Trustwave SpiderLabs

Stay Ahead with Layered Defense

Trustwave MailMarshal Integrated Cloud offers a modern, API-led path to strengthen email defenses within Microsoft 365. By layering MailMarshal’s advanced detection capabilities on top of Microsoft’s native protection, organizations gain a powerful edge in preventing data breaches, safeguarding employees, and reducing operational risk.