RunSybil Raises $40M to Scale AI-Native Offensive Security Testing Platform

Autonomous Hacking at Scale

RunSybil announced a $40 million Series A funding round led by Khosla Ventures to accelerate the development of its AI-native offensive security platform. The investment includes participation from the Anthology Fund, Conviction, and prominent tech leaders such as Jeff Dean and Nikesh Arora. The company plans to use the capital to deepen its engineering efforts and expand its global market reach. The startup, founded by former OpenAI and Meta security experts, provides a black-box testing solution that does not require access to source code. Its flagship platform, Sybil, utilizes autonomous AI agents to explore infrastructure and find exploitable paths just as a human attacker would. This approach addresses the visibility gap left by traditional scanners that often miss how vulnerabilities can be chained together across different systems.

Expert Logic in an AI Agent

CEO Ari Herbert-Voss, OpenAI’s first security hire, notes that legacy tools typically only test what they are told to look at. By contrast, Sybil reasons like a researcher to discover forgotten endpoints and probe authentication boundaries dynamically. CTO Vlad Ionescu previously led Meta’s Offensive Security Group, bringing high-level red teaming experience to the platform’s autonomous logic. Early adopters like Notion and Cursor report that the platform reduces false positives by over 90 percent compared to standard scanning tools. In one instance, the AI successfully chained a low-severity flaw into a critical unauthenticated data access point on a major financial platform. These results demonstrate the efficiency of persistent, automated offensive testing over manual annual audits. More information can be found at runsybil.com. With the new funding, RunSybil aims to bridge the gap between expensive manual penetration testing and inconsistent bug bounty programs. The company is actively hiring researchers and engineers to meet the increasing demand from Fortune 500 enterprises. As software complexity grows, the team remains focused on providing continuous, automated coverage for modern digital infrastructure.