James C. Foster
Chief Executive Officer
James C. Foster is a globally recognized cybersecurity entrepreneur and executive with more than two decades of experience building and scaling security companies. As CEO of eSentire, he leads the company’s mission to deliver world-class managed attack, detection, and response capabilities and protect organizations from sophisticated cyber threats.
Foster is best known as the founder and former Chairman and CEO of ZeroFox, where he built and took public the industry’s leading external cybersecurity platform. During his tenure, ZeroFox achieved more than 30 consecutive quarters of ARR growth, expanded across four continents, completed five strategic acquisitions, and grew into a multi-hundred-million-dollar enterprise protecting thousands of organizations worldwide.
Earlier, Foster founded Ciphent, one of the fastest-growing cybersecurity companies in the United States, serving more than 1,000 enterprise customers—including 43 of the Fortune 100—before merging with Accuvant (now Optiv). He later helped scale Accuvant during a period of rapid growth toward $500 million in annual sales.
Foster has also held leadership roles at Guardent (acquired by VeriSign), Foundstone (acquired by McAfee), Information Security (acquired by Tech Target), and IronCircle (acquired by QuickStart), and began his career supporting national security initiatives at the U.S. Department of Defense.
He is a published cybersecurity author, holds several patents, was the EY Entrepreneur of the Year® and frequently speaks at industry events including RSA Conference, Black Hat, and Rebellion.