Horizon3.ai Raises $73M to Lead the Future of AI-Driven Autonomous Penetration Testing

Horizon3.ai underscores a bold leap in cybersecurity, aligning its capital raise with the urgent need for real-time, scalable defenses. The $73 million funding round not only validates its autonomous pen testing vision, but it also empowers the company to accelerate product innovation, push global expansion, and stay ahead as the attack surface grows ever more complex.

In a pivotal move for enterprise security, Horizon3.ai has closed $73 million in equity financing to supercharge its AI-powered autonomous penetration testing platform.

This round is led by marquee investors, including Craft Ventures and SignalFire, reinforcing strong confidence in Horizon3’s trajectory.

The new capital will support three core growth pillars: expanding its engineering and sales teams globally, accelerating integrations with cloud and regulatory frameworks, and advancing its autonomous security platform to meet increasing demand.

What is Horizon3.ai and NodeZero?

Horizon3.ai’s flagship offering is NodeZero, its autonomous pentesting (penetration testing) platform that simulates attacker behaviors, without scripts, to chain together exploitable attack paths across internal and external environments.

The platform’s capabilities include:

• Discovering exploitable weak points across assets, configurations, and credentials
• Prioritizing paths based on real impact to guide remediation
• Offering proof-of-exploit and remediation guidance
• Enabling continuous find-fix-verify loops rather than periodic tests

Unlike manual pen tests that take weeks and are infrequent, NodeZero operates continuously, effectively scaling offensive testing across the enterprise.

“From Snapshot to Continuous Defense”

Horizon3’s vision is to shift security teams from reactive checklists to proactive resilience. It's Cyber Terrain Map, a knowledge graph that models attack chaining, learns from every execution, and improves its collective intelligence over time.

“We built autonomous pentesting so organizations can see themselves through the eyes of an attacker and remediate what actually matters,” says the Horizon3 team.

Market Traction & Momentum

Horizon3 is gaining broader industry adoption: NCC Group now integrates NodeZero into its services offering. NodeZero has surpassed 100,000 autonomous pentests conducted, a significant milestone for proof of scale.

On the funding side, this round brings Horizon3 closer to a $100M target, with NEA as a lead investor in the broader raise. Earlier, in August 2023, Horizon3 raised $40M in a Series C led by Craft Ventures with participation from SignalFire, bringing its total funding history to ~$78.5M before this round.

Why This Moment Matters

The timing couldn’t be more critical. Cyberattacks now cost enterprises over $1 trillion annually. At the same time, regulatory regimes are tightening: the EU’s NIS2, DORA, and U.S. cyber risk mandates demand real-time reporting for breach and remediation. Horizon3’s autonomous testing offers audit-ready insights and continuous validation.

Autonomous pen testing turns cybersecurity from a cost burden into a growth enabler, enabling organizations to prove defensibility and ensure governance in a dynamic threat landscape.

Meet the Founders & Visionaries

Horizon3.ai was co-founded by Snehal Antani and Anthony Pillitiere, drawing on backgrounds spanning enterprise tech and national security.

Their aim: to build a security system that is “humans by exception”, letting automation handle routine testing while freeing teams to focus on strategy.

Execweb congratulates Horizon3.ai and its leadership on closing this $73M equity round. This funding milestone affirms their position at the forefront of AI-driven, autonomous cybersecurity, a leap that may well redefine how organizations defend in the years ahead.