Adaptive Security Raises $81 Million Series B to Combat AI-Powered Cyber Threats

Adaptive Security, a New York-based cybersecurity company focused on AI-powered social engineering prevention, has rapidly grown its funding base as organizations confront increasingly sophisticated deepfake, phishing, and impersonation threats enabled by generative AI. Since its public launch in January 2025, the startup has secured multiple venture financing rounds from top-tier investors, highlighting strong belief in its mission to equip enterprises with advanced defense tools in the emerging AI threat landscape.

In December 2025, Adaptive Security closed an $81 million Series B funding round to scale its platform and enhance AI-driven capabilities designed to stop AI-powered cyber threats such as deepfake persona attacks across voice, SMS, email, and other channels. The Series B brought the company’s total capital raised to approximately $146.5 million, underscoring rapid investor momentum in a domain where traditional cybersecurity solutions struggle to address the evolving threat environment.

The Series B round was led by Bain Capital Ventures, a global venture capital firm with deep experience backing enterprise software and security companies. Joining Bain in the financing were several notable strategic and technology investors, including NVentures (NVIDIA’s venture capital arm), the OpenAI Startup Fund, Andreessen Horowitz, Abstract Ventures, Capital One Ventures, and Citi Ventures — reflecting broad support across growth investors and corporate backers.

Adaptive Security’s Series B comes on the heels of a highly active Series A cycle earlier in 2025. In April 2025, the company announced a $43 million Series A funding round co-led by Andreessen Horowitz and the OpenAI Startup Fund, marking the first time OpenAI’s venture arm invested in a cybersecurity startup. That initial financing included participation from Abstract Ventures, Eniac Ventures, CrossBeam Ventures, K5, and prominent individual investors from companies such as Google, Workday, Shopify, Plaid, and Paxos.

In September 2025, Adaptive Security also secured a follow-on investment from the OpenAI Startup Fund, bringing its Series A total to roughly $55 million and reinforcing OpenAI’s continued confidence in the company’s AI-centric approach to cybersecurity.

Founded by CEO Brian Long and co-founder Andrew Jones, Adaptive Security emerged in response to the rapid escalation of AI-enabled social engineering attacks, which leverage generative models to craft deeply realistic impersonations of trusted individuals. The founders — veterans of enterprise technology and security — built the company’s platform to combine advanced AI-generated attack simulations, real-time risk assessment, dynamic security awareness training, and executive risk scoring into a unified solution that helps organizations proactively defend against sophisticated threats.

Adaptive’s rapid customer adoption underscores the urgency enterprises feel around AI-driven security challenges. The company now serves more than 500 enterprise customers, including major organizations across sectors such as financial services, technology, healthcare, sports, and entertainment. Notable customers reported include PayPal, Xerox, Bose, Figma, Ramp, Vimeo, the National Hockey League, and the Professional Golfers’ Association, among others — a testament to the broad appeal and enterprise relevance of its defensive platform.

Investors backing Adaptive Security have emphasized the company’s positioning at the forefront of a new generation of cybersecurity solutions. Bain Capital Ventures highlighted the importance of AI-native approaches that can keep pace with evolving attacker tactics, while the OpenAI Startup Fund noted that defending against generative AI abuse requires equally advanced AI-based defenses. Strategic participation from NVIDIA and corporate venture groups like Capital One Ventures and Citi Ventures further underscores the cross-industry relevance of Adaptive’s technology as businesses modernize their security postures.

The funding will enable Adaptive Security to deepen its product innovation, scale its security research and engineering teams, and expand global go-to-market execution to support a widening base of enterprise clients. The company also plans to enhance real-time threat modeling, personalized training modules, and integration with existing security operations ecosystems, all aimed at helping organizations reduce risk exposure in an era where generative AI makes social engineering attacks more convincing and harder to detect.

Adaptive Security’s funding trajectory — from its seed and Series A rounds to its substantial Series B — reflects a broader shift in cybersecurity investment toward AI-first platforms capable of both anticipating and neutralizing AI-driven threats. As adversaries increasingly leverage generative technologies to bypass traditional controls, the company’s investor base and capital runway position it to be a key player in safeguarding digital environments against the next frontier of cyberattacks.