Publicly traded email security provider Mimecast Ltd has bought Solebit Inc., a startup focused on fending off zero-day attacks that target users via their inboxes.

The deal, which was announced this morning, is valued at $88 million net of acquired cash. San Francisco-based Solebit previously raised $13 million in funding from investors. It’s a graduate of Microsoft Corp.’s ScaleU accelerator program and counts insurance giant MassMutual Co. among its backers.

The deal buys Mimecast the startup’s SoleGate cybersecurity platform. The software automatically scans the emails that enter an organization’s network for malicious links and files, with an emphasis on the latter.

Solebit has created a specialized threat detection engine to look for suspicious items inside email attachments. According to the startup, the software works by checking each line of code in a file for hidden processor instructions, malicious macros and other types of malware. It claims that the built-in evaluation mechanisms are thorough enough to detect “zero-day” threats not previously detected elsewhere.

Mimecast already offers Solebit’s software to customers. SoleGate is integrated into its Targeted Threat Protection product line, which includes tools for fending off attacks such as phishing campaigns and malicious attachments.

By acquiring Solebit, Mimecast can take a solution that is effectively already part of its portfolio in-house and remove the possibility of a competitor swooping in. The deal builds on the company’s purchase of Ataata Inc. earlier this month. Ataata developed a cloud-based platform that enables organizations to train employees on how to recognize and avoid online threats.

Mimecast’s effort to beef up its security capabilities comes amid an increase in email-based attacks against enterprises. According to an industry survey that the company published in May, over 90 percent of organizations were targeted by a phishing campaign during 2017.

Moreover, 60 percent of respondents said they expect to suffer a “negative business impact” this year due an email-based attack. Judging by this data, Mimecast’s push to expand its security portfolio comes at a good time from a strategic standpoint.

Image: Mimecast