Armadin hits $2.5B valuation with $255.5M Series B seven months after launch
What's the deal? Armadin, an AI-native cybersecurity company, has raised $255.5 million in a Series B co-led by Andreessen Horowitz and Accel, lifting its valuation above $2.5 billion. New investors Bain Capital Ventures and Redpoint joined, alongside returning backers 8VC, Ballistic VenturesDealroom has a profile for this one. Try Dealroom →, Google VenturesDealroom has a profile for this one. Try Dealroom →, In-Q-Tel, Kleiner Perkins, and Menlo Ventures. The round brings total funding to $445 million.
What's the endgame? Armadin builds what it calls effective autonomous security: a swarm of specialised AI agents that act like adversaries, chaining low-severity weaknesses into validated attack paths. Those chains run from remote code execution at the perimeter through to full cloud compromise, showing security teams exactly how an attacker would break in.
Why now? As frontier AI models shrink the gap between vulnerability disclosure and working exploit, periodic penetration tests cannot keep pace. "AI lets an attacker find and chain weaknesses faster than any human team can respond," said chief executive officer Kevin Mandia.
What's the money for? Armadin will scale its agentic security platform along with its research, training, and go-to-market efforts. Seven months after leaving stealth, it is already running attack campaigns in production for Fortune 500 enterprises and government customers.
By the numbers: The round ranks in the 99th percentile of all-time Series B rounds for US security companies, among a sample of 1,066 deals — a scale that reflects how quickly AI is compressing startup timelines.
The signal: Investors are betting that offence, not defence, defines the next security era. "Every major platform shift creates a new generation of security leaders, and AI is the biggest shift we've seen," said David George, general partner at Andreessen Horowitz. Backing a founder with Mandia's breach-response track record, they are wagering that AI-driven attacks demand AI-driven red teams to match them.
Read more: prnewswire.com
Image credit: Armadin
