Autonomous security solutions startup Horizon3.ai Inc. today announced it has raised $100 million in new funding to scale up its partner ecosystem, expand platform capabilities and accelerate adoption in the U.S. federal market.

The company was founded in 2019 by former Splunk Inc. Chief Technology Officer Snehal Antani and Anthony Pillitiere, former deputy CTO within U.S. Special Operations Command. It offers automated penetration testing designed to allow companies to see themselves through the eyes of an attacker. Pentesting is the practice of simulating cyberattacks on a system, network or application to identify vulnerabilities before malicious hackers can exploit them.

Horizon3.ai’s platform, called NodeZero, is an artificial intelligence-powered autonomous pentesting platform that continuously and safely emulates real-world cyberattacks across your network and cloud environments. NodeZero autonomously discovers and exploits vulnerabilities, such as weak credentials, misconfigurations or exposed services, by chaining together attack paths just like a human hacker would, but with machine-scale speed and without scripts.

NodeZero goes beyond traditional vulnerability scanning by actively executing full attack chains and post-exploitation actions, including lateral movement, privilege escalation and data exfiltration without the need for human input. The platform then provides actionable insights into what could be compromised and how to fix it, enabling security teams to prioritize and verify remediations based on real threat exposure rather than hypothetical risks.

In the words of Horizon3.ai, “NodeZero doesn’t simulate adversaries — it thinks and acts like one.” Each cyberattack against production systems executed by NodeZero collects training data used to improve its algorithms, creating a compounding data advantage that it claims no other platform can match.

Horizon3.ai said it has seen strong growth, with annual recurring revenue up 100% year-over-year, off an undisclosed base. More than 3,000 organizations use NodeZero to conduct penetration tests.

The Series D round was led by New Enterprise Associates Inc., with SignalFire, Craft Ventures Management and 9Yards Capital also participating. As part of the funding deal, Lila Tretikov, partner and head of AI strategy at NEA and former deputy CTO of Microsoft Corp., will join the Horizon3.ai board.

“What drew us to Horizon3.ai is the clarity of their mission and the speed at which they’re executing it,” said NEA Partner Aaron Jacobson said in a statement. “They are defining a new security category — autonomous security — and are already the go-to solution for red and blue teams alike.”

Image: Horizon3.ai