Cybersecurity startup Horizon3 has raised a $250 million Series E at a $2 billion valuation, according to TechCrunch, which reported the round as AI-driven security threats escalate.
The company's product is called NodeZero. As Techmeme summarized reporting by Kate Park at TechCrunch, the platform uses AI to find and exploit attack paths in production systems — meaning it doesn't just flag theoretical weaknesses on a checklist, it attempts to chain them together and break in, on the live systems a business actually runs.
That is essentially automated penetration testing. Traditionally, a "pentest" is a scheduled engagement in which a company hires human hackers to attack its own defenses and write up what they found. It is expensive, labor-intensive, and for many organizations happens roughly once a year.
TechCrunch frames the funding around exactly that gap: companies increasingly want continuous, AI-powered security validation rather than annual pentesting. A once-a-year snapshot says little about the other 364 days, during which code ships, cloud configurations drift, and new vulnerabilities surface.
The scale of the round is its own signal. A $250 million Series E at a $2 billion valuation is late-stage money at a size usually reserved for companies investors expect to keep compounding, and it lands in a market where attackers are also adopting AI — one of the dynamics TechCrunch cites as escalating.
Why it matters: if AI can continuously attack a company's own systems the way real intruders would, security shifts from a periodic audit that quickly goes stale to an always-on check — and the money flowing into Horizon3 suggests investors believe that shift is already underway.