AI Security for Autonomous Agents and Shadow AI: The Rise of Defensible Infrastructure-Layer Solutions

The AI security landscape is undergoing a seismic shift. As autonomous agents and shadow AI proliferate, enterprises are confronting a new frontier of risks that demand infrastructure-centric solutions. The market for AI security infrastructure is projected to grow from $8.63 billion in 2024 to $79.73 billion by 2034, driven by a 32.2% CAGR, while the autonomous agents market alone is expected to expand at a blistering 42.8% CAGR, reaching $70.53 billion by 2030. These figures underscore a trillion-dollar opportunity, but the real story lies in the transition from model-centric security to infrastructure-layer defenses-a shift validated by the rapid rise of startups like Witness AI and Multifactor.

The Infrastructure-Centric Imperative

Traditional cybersecurity frameworks, designed for static systems, are ill-equipped to handle the dynamic, decentralized nature of AI workflows. Autonomous agents-AI systems capable of independent decision-making-introduce vulnerabilities through unmonitored interactions, data sharing, and behavioral drift. Meanwhile, shadow AI-the use of unsanctioned AI tools within organizations-has become a critical risk vector, with 77% of companies experiencing breaches in their AI systems in 2025.

The solution lies in securing the infrastructure layer: the pipelines, protocols, and governance frameworks that govern AI operations. This includes monitoring agent behavior, enforcing compliance with regulatory standards like the EU AI Act, and mitigating threats such as prompt injections and rogue Model Context Protocol (MCP) servers. According to a report by Grand View Research, the AI governance market is projected to grow from $620 million in 2024 to $7.38 billion by 2030, reflecting the urgent demand for infrastructure-layer solutions.

Witness AI: Scaling AI Agent Security at Enterprise Speed

Witness AI has emerged as a leader in this space, securing $58 million in funding led by Sound Ventures and Qualcomm Ventures to accelerate its global expansion. The company's platform offers two-way observability into AI agent actions, enabling enterprises to detect misaligned behaviors and block malicious prompts before they execute. This capability is critical as AI workflows evolve: for instance, a 2025 case study demonstrated how Witness AI's red-teaming exercises uncovered vulnerabilities in prompt injection attacks, preventing potential data exfiltration in a financial services firm.

The startup's ARR has grown over 500% year-over-year, a testament to its value proposition in high-stakes industries like finance, automotive, and telecommunications. Its focus on agentic AI governance-tracking agent interactions with MCP servers and ensuring alignment between prompts and actions-positions it to capitalize on the $52.62 billion AI agents market by 2030.

Multifactor: Securing the Future of AI Credential Access

While Witness AI targets agent behavior, Multifactor addresses a foundational infrastructure risk: secure credential management. The startup recently raised $15 million in seed funding, led by Nexus Venture Partners and Y Combinator, to develop post-quantum security solutions for AI agents. Its platform allows organizations to share online accounts securely without exposing credentials-a critical feature as AI agents increasingly access sensitive systems.

Real-world threats like "LLMjacking"-where attackers steal API keys to access large language models-highlight the urgency of Multifactor's approach. In 2025, a Microsoft lawsuit revealed a gang exploiting such vulnerabilities, underscoring the need for cryptographic solutions to prevent credential theft. Multifactor's ARR growth is poised to benefit from the broader AI-native software development boom, with tools like Cursor and Replit scaling to $500 million and $100 million ARR, respectively.

The Trillion-Dollar Market: A Convergence of Trends

The convergence of AI infrastructure growth, autonomous agent adoption, and shadow AI risks creates a self-reinforcing cycle of demand. By 2030, the AI infrastructure market is projected to reach $223.45 billion, driven by cloud-based AI platforms and high-performance computing needs. Meanwhile, the AI governance and security segment is growing at a 51% CAGR, outpacing even the broader AI infrastructure market.

Startups like Witness AI and Multifactor are uniquely positioned to dominate this landscape. Their competitive advantages-backed by $58 million and $15 million in funding, respectively-include:
- First-mover access to enterprise clients in high-growth sectors.
- Real-world threat validation, with case studies demonstrating mitigation of prompt injections, data poisoning, and credential theft.
- Scalable infrastructure-layer solutions that align with regulatory frameworks like NIST's AI Risk Management Framework.

Conclusion

The AI security market is no longer a niche-it is a trillion-dollar inevitability. As autonomous agents and shadow AI redefine enterprise risk, infrastructure-layer solutions will become the bedrock of digital trust. Witness AI and Multifactor exemplify the next generation of security providers, leveraging venture capital, ARR growth, and real-world threat intelligence to build defensible moats. For investors, the lesson is clear: the future of AI security lies not in models, but in the infrastructure that governs them.