Kevin Mandia’s offensive security startup has closed one of the year’s largest cybersecurity funding rounds, less than a year after it came out of stealth.
Andreessen Horowitz and Accel co-led the Series B, which values Armadin at more than $2.5 billion. Bain Capital Ventures and Redpoint joined as new investors, while 8VC, Ballistic Ventures, Google Ventures, In-Q-Tel, Kleiner Perkins, and Menlo Ventures returned. The $255.5 million round lifts Armadin’s total funding to $445 million.
Armadin’s own account is that Fortune 500 companies and government agencies already receive agentic attack campaigns from it in a live production setting. Behind its platform sits a swarm of specialized agents that reason across a target’s attack surface and stitch individually low-severity flaws into validated kill chains, which then run from unauthenticated remote code execution at the perimeter through lateral movement to full cloud compromise, handing defenders the whole path. Security teams also learn each chain’s blast radius, so they can sever them first.
Mandia argues that offense holds the advantage. His case is that an intruder backed by AI spots and chains weaknesses at a pace no human defensive team can match. Accel partner Ping Li said the firm’s bet on Armadin was that a strong AI-driven offense is the best answer to agentic adversaries. Andreessen Horowitz’s David George said Mandia has assembled a team that pairs elite red teamers with top AI engineers. Armadin will spend the money scaling its platform, research, training, and go-to-market teams.
