HedgeCo.Net — Armadin, the AI-native cybersecurity company led by Mandiant founder Kevin Mandia, said on October 1, 2026 that it raised $255.5 million in Series B funding at a valuation of more than $2.5 billion. Andreessen Horowitz and Accel co-led the round, with new participation from Bain Capital Ventures and Redpoint. Existing investors including 8VC, Ballistic Ventures, Google Ventures, In-Q-Tel, Kleiner Perkins, and Menlo Ventures also returned. The company said total funding now stands at $445 million after a $190 million Series A earlier in 2026.
Armadin markets always-on agentic attack campaigns that chain vulnerabilities into validated kill chains for Fortune 500 and government customers, positioning the product as a continuous alternative to periodic penetration tests. Mandia said AI has advantaged offense and that defense must train against strong offense every day. Accel’s Ping Li and a16z’s David George both framed Armadin as a defining security platform for the AI era in comments carried in the company release; TechCrunch independently reported the round size, valuation, and investor list.
The seven-month path from stealth Series A to a >$2.5 billion Series B is an aggressive venture print even by cyber standards. Armadin said proceeds will scale the agentic platform plus research, training, and go-to-market. Andreessen Horowitz published a separate investing note confirming its participation.
For venture and growth allocators, the story is less about a novel category label than about whether continuous agentic red-teaming can convert into durable enterprise ARR at cyber-scale valuations. Diligence should test customer concentration, proof of remediation outcomes versus scan volume, and how quickly the $445 million cumulative raise translates into durable gross margins.