
This week's developments show AI's growing role in both security offense and defense, moving beyond simple models to complex agentic systems. The focus is shifting to the tooling, infrastructure, and intent that define these systems. Security firm Trail of Bits shared how it used AI agents to build a complete security auditing suite for a new technology, finding critical flaws. Meanwhile, researchers from Palo Alto Networks and Wiz highlight new risks in agent infrastructure and foundational cloud posture, and new methods for detecting malicious agent behavior.
AI as a Bespoke Tool-Builder Finds Critical Flaws
Security firm Trail of Bits reported on its extensive use of AI agents to prepare for a security review of the Miden VM. This new zero-knowledge virtual machine uses a custom assembly language, MASM, which had almost no developer tooling available. This presented a significant challenge for a deep security audit, as auditors would lack basic features like syntax highlighting, code navigation, and static analysis.
Over a six-month preparation period, the firm tasked its AI agents with building a complete suite of custom tools. The AI-driven effort produced an LSP server for VS Code, a decompiler, a static analysis engine, and a formal Lean model of the VM executor. This work involved multiple AI models for development and code review, generating over 100 commits for the decompiler alone [1].
The custom-built tooling yielded significant results during the actual review. The static analysis engine identified over 400 locations where type validation could be improved. It also uncovered a high-severity finding where an unvalidated input from a prover could be used to forge signatures and steal funds. The formal modeling work also identified two subtle bugs that the existing unit test suite had missed.
This project demonstrates a new frontier for AI in security. The firm stated that such an exploratory and resource-intensive tooling project would have been economically unfeasible just a few years ago. AI agents made it possible by dramatically lowering the cost of development. The success of the project shows AI's potential not just as a code reviewer, but as a force multiplier for creating highly specialized, high-assurance security tools.
Securing Credentials in AWS AgentCore Harness
AI agents need credentials to interact with other systems and perform useful tasks. A report from Unit 42 analyzed the security implications of default configurations in the AWS AgentCore Harness, a framework for building these agents. The research highlights the critical space between an agent's core logic and the identity it uses to access resources [2].
The primary risk involves the potential for prompt injection attacks to exfiltrate credentials. If an attacker can trick an agent into revealing its access tokens or keys, they can bypass other security controls. The agent effectively becomes a confused deputy, using its legitimate authority to perform malicious actions on the attacker's behalf.
A compromised agent with broad permissions poses a significant threat. It can serve as a pivot point for an attacker to move deeper into a cloud environment. This elevates a prompt injection attack from a localized issue into a potential full-scale breach. Securing the agent's identity is therefore as important as securing the model itself.
Defenders must implement security controls that go beyond default settings. The report suggests enforcing the principle of least privilege through tightly scoped IAM policies. Using temporary credentials that expire quickly can limit the window of opportunity for an attacker. Continuous monitoring of agent activity for anomalous API calls or data access patterns is also essential for detecting a potential compromise.
The Modern SOC and the Cross-Environment Pivot
Attackers rarely stay in one place. Modern security incidents often involve attackers moving across different environments, such as from a corporate network to the cloud, or from a traditional server to an AI workload. Unit 42 research highlights the challenge this presents for Security Operations Centers (SOCs) trying to track and contain threats [3].
AI-powered security platforms are becoming essential for defending against these complex attacks. By correlating alerts and logs from disparate sources, these systems can piece together a complete attack path. This gives analysts the context they need to understand the full scope of an incident, rather than viewing each alert in isolation.
The agentic angle is critical in this context. A compromised AI agent, as described in the AWS AgentCore scenario, could be the first step in a larger cross-environment attack. An attacker might use the agent's credentials to access a database, then use that access to pivot to another part of the cloud infrastructure. A modern SOC must be able to detect this entire chain of events.
This reality requires a shift in security operations. SOC teams need unified visibility and detection capabilities that span their entire technology stack, including AI systems. Playbooks must be updated to account for agent-driven threats, and analysts need the tools to investigate the behavior of AI agents alongside traditional endpoints and network traffic.
Foundational Cloud Posture for AI Workloads
The security of any AI system is built upon the security of its underlying cloud environment. A recent analysis from Wiz explored the new AWS account sign-up experience, emphasizing that initial configurations create a lasting security posture. Weak foundations can put even the most advanced AI workloads at risk [4].
The report notes that new account experiences often include a "sandbox" to help users get started quickly. While convenient, these sandboxed environments may lack the strong controls necessary for production systems. Deploying a powerful AI agent with broad permissions into an account with default, insecure settings is a recipe for a breach.
Researchers stress the importance of moving beyond these initial configurations before deploying sensitive workloads. Establishing a strong security baseline is not optional. This includes enforcing multi-factor authentication, configuring least-privilege IAM roles, enabling comprehensive logging, and setting up continuous monitoring from the very beginning.
For organizations building and deploying AI, this is a critical lesson. An AI agent is a high-value target. Attackers will not only target the model with prompt injection but will also probe the surrounding cloud infrastructure for weaknesses. Securing the agent starts with securing the account it lives in.
Building Detection Engines That Understand Agent Intent
As AI agents gain more autonomy, distinguishing between legitimate and malicious actions becomes a major security challenge. A blog post from Wiz argues that traditional security tools are not equipped to handle this new threat landscape. A new approach is needed to detect malicious agent behavior [5].
The proposed solution is an AI-native detection pipeline designed to understand an agent's intent. This system would use AI to analyze the behavior of other AI agents. By ingesting and analyzing the input prompts, output logs, and API calls associated with an agent, the detection engine can build a model of its behavior over time.
This approach moves beyond simple signature matching. Instead, it focuses on identifying sequences of actions that indicate malicious intent. For example, a benign agent might access a sensitive file, but a malicious one might do so after a suspicious prompt, then attempt to exfiltrate data via obfuscated API calls. The detection engine is trained to spot these multi-step patterns.
This represents a necessary evolution in AI defense. It shifts the security posture from being purely reactive to proactive. By understanding and flagging malicious intent before an attack fully executes, defenders can block harmful agentic workflows. This capability is a cornerstone for building and operating trustworthy autonomous systems at scale.
Common Threads
This week's stories reveal a clear focus on the systems and infrastructure that underpin AI agents. We are moving past the initial novelty of large language models and into the engineering challenges of deploying them safely and effectively. Trail of Bits' work shows AI as a powerful tool for building security infrastructure, while reports from Unit 42 and Wiz highlight the new security infrastructure needed to manage AI agents. The common theme is professionalization: AI is becoming a core, engineered component of the tech stack, demanding a new level of rigor in how we build, secure, and monitor it.
Defender Takeaway
The rise of agentic systems requires defenders to think beyond the model and secure the entire operational loop. This means scrutinizing the agent's identity, the tools it can access, the data it handles, and the cloud environment it inhabits. An agent with excessive permissions is a latent vulnerability. A strong foundational security posture, combined with continuous monitoring of agent behavior, is the most effective defense against this new class of threats.
OPERATOR ACTION
Review and harden the IAM permissions for all deployed AI agents and the services they can access.
References
- blog.trailofbits.com. https://blog.trailofbits.com/2026/09/18/auditing-in-the-age-of-good-enough-ai/ (accessed 2026-09-20).
- unit42.paloaltonetworks.com. https://unit42.paloaltonetworks.com/securing-aws-agentcore-harness-credentials/ (accessed 2026-09-20).
- unit42.paloaltonetworks.com. https://unit42.paloaltonetworks.com/soc-cross-environment-pivot/ (accessed 2026-09-20).
- wiz.io. https://www.wiz.io/blog/exploring-the-new-aws-sign-up-experience (accessed 2026-09-20).
- wiz.io. https://www.wiz.io/blog/building-an-ai-detection-engine-for-agent-intent (accessed 2026-09-20).
About Helixar Research Labs
Helixar is an AI-native software R&D lab focused on agentic governance, compliance, and security for enterprises and enterprise agents.
Helixar Research Labs publishes briefings on the agentic and AI threat surface, including autonomous agents, LLM tooling, MCP servers, model supply chains, and prompt injection. The goal is to surface the gap between traditional defenses and agentic attacks before it shows up in your incidents.
If you run agents in production, this is for you. Learn more at helixar.ai.