Armadin

Cybersecurity · Artificial Intelligence

Funding

Armadin raises $255.5M Series B at $2.5B valuation 7 months after stealth

Its autonomous agents run live attack simulations against Fortune 500 networks, racing the same AI speed that now favors attackers.

• Armadin raised $255.5 million in a Series B round co-led by Andreessen Horowitz and Accel, valuing the AI cybersecurity startup at more than $2.5 billion just seven months after leaving stealth.
• Founded by Mandiant creator Kevin Mandia, Armadin builds an AI-native platform that runs autonomous 'agentic' attack campaigns against enterprise and government networks to find exploitable paths before real attackers do.
• The raise brings Armadin's total funding to $445 million since its stealth launch earlier this year.
• Armadin's autonomous agent swarm reasons like an adversary, chaining individually low-severity weaknesses into validated kill chains that run from perimeter remote code execution to full cloud compromise.
• Investors are pouring money into early-stage startups building defenses against AI-driven cyberattacks, as frontier models compress the gap between vulnerability discovery and working exploits.
• The rapid re-rating shows how AI-security startups are being valued on offense-defense speed, turning periodic pentesting into a liability as attackers move faster than humans can respond.