RunSybil raised $40M

RunSybil was co‑founded in 2023 by Ari Herbert‑Voss (CEO), who joined OpenAI as its first security research hire in 2019, and Vlad Ionescu (CTO), previously responsible for offensive security/red‑team work at Meta. (runsybil.com/post/runsybil-raises-40m-to-build-the-ai-native-platform-for-offensive-security) The company’s flagship agent, named Sybil, performs continuous black‑box penetration testing that dynamically explores authentication boundaries, discovers forgotten endpoints, chains vulnerabilities together, and runs live exploit validation. (runsybil.com/post/runsybil-raises-40m-to-build-the-ai-native-platform-for-offensive-security) RunSybil cites early deployments at startups and larger customers including Cursor, Notion, Turbopuffer and Thinking Machines Lab, alongside several unnamed Fortune 500 firms. (builtinsf.com/articles/runsybil-raises-40m-funding-20260318) The recent financing attracted strategic backers beyond the lead, with participation from S32, the Anthology Fund (Anthropic/Menlo), Menlo Ventures, Conviction and investor Elad Gil, plus angels such as Nikesh Arora, Amit Agarwal and Jeff Dean. (runsybil.com/post/runsybil-raises-40m-to-build-the-ai-native-platform-for-offensive-security) RunSybil says customers report more than a 90% reduction in false positives versus conventional scanners, and the platform supports replayable attack paths so teams can verify remediation end‑to‑end. (runsybil.com/post/runsybil-raises-40m-to-build-the-ai-native-platform-for-offensive-security) Company statements and press coverage specify proceeds will be used to accelerate engineering hiring, expand security research capabilities, and fund go‑to‑market expansion. (builtinsf.com/articles/runsybil-raises-40m-funding-20260318)