Synack, a cybersecurity startup that helps businesses prevent and counter security breaches, announced today new funding of $21.25 million, led by Microsoft Ventures.

Synack’s core product, Hydra, scans a business or organization’s IP and alerts researchers of possible vulnerabilities, changes, or unknown events. Researchers then validate known vulnerabilities or investigate potential attack vectors.

Synack’s cofounder and CEO, Jay Kaplan, claims to have an edge over other cybersecurity companies — a global network of vetted hackers.

“We have an extremely rigorous vetting approach, using interviews, background checks, skills assessments, and more,” Kaplan wrote in an email to VentureBeat. “We have a passport for every researcher in our network on file, a far cry from the open, public bug bounty programs where all you need is an email address to sign up.” Regarding payment, “We pay our researchers well and we do it within 24 hours of a vulnerability being verified,” he wrote.

Synack says it has hundreds of customers, including The Pentagon and the Department of Defense. Prices range from fixed fees for penetration tests to a fixed monthly subscription for continuous testing.

Regarding competition, Kaplan claims to be quite different from HackerOne and Bugcrowd. “We are not a marketplace matching unvetted researchers with customers,” he wrote. “We are a full service security solution.”

Hewlett Packard Enterprise and Singtel Innov8 joined Microsoft Venture in today’s round. Existing investors GGV Capital, GV (formerly Google Ventures), and Kleiner Perkins Caufield & Byers also joined. This brings Synack’s total funding to over $55 million.

The new money will be used to further develop the product, scale adoption across the U.S. and Europe, enter the Asia Pacific region, and continue to recruit hackers.

Founded in 2013, the Redwood City, Calif.-based startup currently has approximately 100 employees.

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