Mimecast and Zscaler Team Up to Tackle Multi-Vector Threats with Integrated Zero Trust Security

Cybercriminals no longer limit themselves to phishing emails. Today’s most damaging attacks exploit a patchwork of communication tools, from cloud collaboration platforms to unmanaged personal accounts. Mimecast and Zscaler are taking aim at this fractured threat landscape with a newly announced technology integration designed to close the gaps between these vectors in real time.

The collaboration between Mimecast, best known for its cloud-based email and collaboration security, and Zscaler, a heavyweight in zero trust architecture, will enable automated threat intelligence sharing between their platforms. At its core, the integration is designed to detect and block malicious activity across environments — before threats can move laterally or escalate.

The strategic move reflects a growing trend in cybersecurity: tackling the cross-platform nature of attacks with a similarly cross-platform response.

“Single-point attacks are a thing of the past in cybersecurity,” said Ranjan Singh, Chief Product & Technology Officer at Mimecast. “Organizations now face sophisticated and targeted threats that leverage multiple entry points to cast a wider net. By integrating with Zscaler, joint customers gain essential threat sharing capabilities that will ensure their employees can work confidently regardless of which tool they’re using.”

That confidence is increasingly critical. According to Mimecast’s 2025 State of Human Risk report, 61 percent of organizations anticipate a damaging attack involving collaboration tools this year. Despite email maintaining its spot as the leading threat vector, attackers are increasingly targeting platforms like Slack, Microsoft Teams, and Google Workspace.

Mimecast already processes seven billion signals across collaboration and email platforms each day. With this integration, threat intelligence — such as a malicious URL blocked in an email — is shared instantly with Zscaler’s Zero Trust Exchange. If an attacker tries to reuse the same domain through a different channel, like a chat app or unmanaged personal device, Zscaler blocks access before the threat progresses.

The benefits extend beyond just threat mitigation. Data loss prevention (DLP) is another shared focus. Zscaler will now analyze both email text and attachments for sensitive content, passing insights to Mimecast, which can apply policy actions ranging from alerts to blocking the message altogether.

“Safeguarding data from ongoing threats in a modern, distributed enterprise requires a comprehensive data protection program and threat management as part of the zero-trust architecture,” said Venkat Krishnamoorthi, Vice President of Product Management at Zscaler. “Through the Zscaler and Mimecast partnership, customers can leverage Zscaler’s industry-leading data protection and security platform to inspect specific email traffic, ensuring it is thoroughly reviewed for sensitive content.”

The companies highlight three core advantages for joint customers: deeper defense, streamlined operations, and uniform data protection. By tapping into Mimecast’s analysis of 1.8 billion emails per day — and blocking nearly five billion malicious messages a month — Zscaler’s security engine gains richer context. Meanwhile, security teams benefit from automation, freeing them from duplicating efforts across disparate platforms.

Ultimately, the Mimecast-Zscaler alliance represents more than just an API handshake. It’s a step toward a more unified cyber defense fabric, one where intelligence moves faster than the attackers. As the lines between communication tools blur, it’s no longer enough to defend one perimeter. The perimeter is everywhere — and so, too, must be the protection.