Tenable Network Security, makers of vulnerability scanners and software solutions that helps find network security gaps, this week announced that it has raised $50 million in its first-round funding from Accel Partners.

The company said it would use the cash boost to expand its security offerings and accelerate global growth, as well as deepening its research into threats.

“Security is a mainstream issue – especially with the explosion of mobile, cloud and virtual computing,” said Ron Gula, CEO of Tenable. “Serious network attacks are far more common than anyone wants to publicly admit – and our customers count on us to keep their networks safe.”

The company’s flagship vulnerability management products ,Nessus and SecurityCenter, are used across more than 15,000 organizations worldwide, including the entire U.S. Department of Defense, where the company said Tenable has become the vulnerability management standard.

Tenable’s SecurityCenter combines active and passive vulnerability scanning, real-time network monitoring, and configuration and compliance management. Tenable’s Nessus vulnerability scanner provides the a deep database of known vulnerabilities and compliance risks to help security teams find gaps before attackers do.

The company said revenue has climbed more than 550% over the past four years, and that it has doubled its staff over the past year to nearly 200 people and expects to double that figure over the next two years.

Along with the investment, Ping Li, General Partner at Accel, will join Tenable’s board of directors.