Armadin, the AI-powered offensive security startup founded by Kevin Mandia, has raised $255.5 million in a Series B round co-led by Andreessen Horowitz and Accel, according to Help Net Security. SecurityWeek reports the figure as $255 million, but both sources agree the valuation is around $2.5 billion and total funding reaches approximately $445 million. The round also included new investors Bain Capital Ventures and Redpoint, with existing backers returning.
The company emerged from stealth only seven months ago and is already running agentic attack campaigns in production for Fortune 500 enterprises and government customers. Armadin deploys an autonomous swarm of specialized agents that reason like a skilled adversary, chaining individually low-severity weaknesses into validated kill chains that can move from unauthenticated remote code execution to full cloud compromise.
Mandia argues that offense is uniquely advantaged right now because AI lets attackers find and chain weaknesses faster than human teams can respond. The funding will be used to scale the platform, research, training, and go-to-market efforts. Investors echo the view that against agentic adversaries, the best defense is a great offense powered by AI.