Onyx Security, a two-year-old startup with offices in Tel Aviv and New York, closed a $113 million Series B round on July 29. AdvertisementOnyx built what it calls an “AI control plane,” essentially a supervisory layer that discovers, monitors, and remediates risks created by AI agents operating across an organization. The platform currently secures more than 1.1 million agents and covers 1.8 million employees. The company previously raised $40 million in March 2026, split between a $35 million Series A led by Conviction and a $5 million seed round from Cyberstarts. Co-founder Maxim Bar Kogan, the CEO, brings a background from IDF Unit 8200, Israel’s elite intelligence technology unit.