Horizon3
Series E+ · Amsterdam
Cybersecurity · B2B · AI-native
Autonomous penetration testing platform
Horizon3 AI builds NodeZero, a platform that runs autonomous penetration tests against production systems without taking them down. Conventional pentesting is periodic, expensive and manual, so most organisations learn about an exposure long after an attacker could have found it. Running the test continuously and safely against live infrastructure changes what a security team can know about its own environment. The team is made up of learn-it-alls rather than know-it-alls, working to a culture of respect, collaboration, ownership and results.
horizon3.ai (opens in a new tab)Last round
$250MSeries EAug 2026
Led by NEA and NightDragon
Recent raisesOpen roles
63 open roles