Kevin Mandia's Armadin raises $255.5M at more than $2.5B valuation

Kevin Mandia, best known as the founder of cybersecurity startup Mandiant — which sold to Google for $5.4 billion in 2022 — has raised $255.5 million for his latest venture, Armadin, at a valuation of more than $2.5 billion, the company announced on Thursday.

The Series B round was led by Andreessen Horowitz and Accel, with Bain Capital Ventures, Redpoint, 8VC, Ballistic Ventures, Google Ventures, In-Q-Tel, Kleiner Perkins, and Menlo Ventures also participating. The new round comes just six months after Armadin raised a $190 million Series A in March, bringing its total funding to more than $445 million.

Armadin sells enterprises a new kind of always-on security by reimagining how defense testing works for the AI era. Instead of traditional penetration tests, where hired security professionals try to break into a system and report on what they find, Armadin runs always-on agentic swarms that chain together vulnerabilities to hack in. The goal is to help organizations find and close holes before bad actors — including AI labs with rogue agents — can turn agentic technology against them.

Why it matters

A valuation of more than $2.5 billion just six months after a $190 million Series A shows how much investor appetite there is for security products built specifically to counter AI-driven attacks, not just AI-assisted defense. Mandia’s track record with Mandiant gives Armadin’s bet on autonomous, always-on “agent swarm” testing an unusually large amount of capital to prove out before rivals catch up.