Armadin, a security startup founded by Mandiant creator Kevin Mandia, raised $255.5 million in a Series B round at a valuation of more than $2.5 billion, according to TechCrunch and Crunchbase News.
Andreessen Horowitz and Accel led the round, with Bain Capital Ventures, Redpoint, 8VC, Ballistic Ventures, Google Ventures, In-Q-Tel, Kleiner Perkins and Menlo Ventures also participating, TechCrunch reported. The Palo Alto, California, company has now raised more than $445 million, including a $190 million Series A round in March, according to TechCrunch.
Armadin runs autonomous AI agent swarms that continuously test enterprise networks, chaining together vulnerabilities to simulate real attacks instead of relying on periodic, human-led penetration tests, TechCrunch reported. The goal is to find and close security gaps before criminals or rogue AI agents find them first, according to the outlet.
Crunchbase News described Armadin as "AI-native" and built around "autonomous security," ranking the round among the week's 10 largest as part of a list dominated almost entirely by AI funding.
Mandia built Mandiant into the company incident responders call when a breach is already underway, then sold it to Google for $5.4 billion in 2022. Armadin is a bet that the same expertise applies before an attacker shows up, using AI agents to find the holes a human red team would need weeks to find.