Rein Security Secures $25 Million to Combat AI Threats for Enterprises

Rein Security Secures $25 Million to Tackle AI Cyber Threats

In a significant financial move, Rein Security, an innovative platform focusing on the security of AI-driven enterprises, has successfully raised $25 million in its Series A funding round. This funding round was co-led by Glilot Capital and Sienna Venture Capital, boosting the company’s total capital raised to $35 million. The surge in funding comes amid a rapid increase in the deployment of AI agents across various business sectors, raising new security challenges that traditional solutions are not equipped to handle.

The AI-native runtime security platform aims to safeguard enterprises against AI agents that can access sensitive business systems, data, and workflows while also protecting against malicious AI attacks. According to research by Gartner, the demand for AI security solutions is expected to soar, with the market projected to reach nearly $4.8 billion by 2027. Rein Security acknowledges that while companies are quickly adopting AI, securing these systems has not evolved at the same pace, leading to significant vulnerabilities.

With a patented sidecar technology, Rein Security is setting itself apart by ensuring that every action an AI agent takes is visible, traceable, and manageable in real-time. This capability is essential for maintaining governance over agents and intervening whenever they act inappropriately. As enterprises increasingly rely on AI, the stakes are higher; these agents are not only taking actions automatically but can also be manipulated by adversarial AI in ways that can compromise systems rapidly.

Matan Bar-Efrat, co-founder and CEO of Rein Security, explained that the new funding will enable the company to further develop the critical infrastructure needed for enterprises to deploy their AI agents safely. He noted, “As AI agents become integral to business operations, it is vital that security measures are not only advanced but also comprehensive enough to mitigate risks.”

The shift toward an agent economy is indeed taking shape, and executives from Glilot Capital and Sienna Venture Capital emphasize the urgent need for new security protocols tailored to these technologies. As AI agents gain autonomy, businesses must pivot from traditional security measures towards more proactive methods focused on prevention and protection.

During recent industry gatherings, including Black Hat USA 2026, Rein Security's vulnerability research team, Agent Breakers, unveiled alarming vulnerabilities within AI shopping agents, demonstrating real-world consequences of insufficient security measures. Their findings are a wake-up call to organizations that AI adaptation is outracing their protective measures, and immediate action is needed.

As global enterprises onboard an increasing number of AI agents, it’s imperative that they adopt advanced security frameworks. The current frameworks are inadequate for managing the transition towards a more AI-integrated operational environment. Thomas Visan from Sienna Venture Capital emphasized this gap, stating, “Rein’s platform is uniquely designed to tackle the evolving threats presented by agentic AI, placing it in a strong position in the rapidly changing market.”

Rein Security plans to leverage its new funding to enhance product innovation and expand its reach across multiple sectors. The company has seen a remarkable growth trajectory, with an 8x increase in revenue and a 5x increase in its customer base since its launch in January 2026. Noteworthy companies, such as Flex and Swimlane, have joined its roster, showcasing Rein’s wide applicability across industries ranging from healthcare to finance.

Additionally, Rein has extended its security services to secure agents for leading organizations like Dun & Bradstreet, ensuring that they can maintain their reputation for reliability and trustworthiness in their data. Jay DePaul, the chief cybersecurity technology risk officer at Dun & Bradstreet, stated, “Rein empowers us with the visibility and control necessary for scaling our AI capabilities without compromising customer security.”

As Rein Security strengthens its position, it has gained recognition in the tech and cybersecurity domains. The company was selected as one of eight early-stage firms for the AI Conference’s Startup Showdown and ranked in TechCrunch’s Startup Battlefield 200 for outstanding innovation in cybersecurity.

To summarize, the recent influx of funding at Rein Security signifies a crucial step toward fortifying AI agent security within enterprises. By investing in innovative protection strategies, Rein is poised to navigate the forthcoming challenges brought forth by AI integration in business environments. For further details, you can explore their offerings at www.reinsec.io.

About Rein Security

Rein Security was established in 2024, aimed at building security solutions tailored for enterprise AI agents. With a patented architecture providing real-time visibility and protection, Rein ensures that every action taken by AI agents is logged and correlated with business outcomes. Backed by premier investors such as Glilot Capital and Sienna Venture Capital, the company has positioned itself as a leader in the emerging field of agentic AI security.