I’ve spent my career navigating the labyrinth of information security, transitioning from in-depth technical audits to the critical work of Generative AI Governance, Risk, and Compliance (GRC). In all that time, I’ve learned one immutable truth: every major paradigm shift in technology creates a corresponding shift in attack strategy. For the past decade, we’ve relied on security training and technology to protect against phishing. I stand here today to tell you that this era is over. The moment we successfully celebrated training our colleagues to spot poorly crafted emails, the adversaries upgraded their entire operational capabilities. The burning question I face now, every day, is this: How do we defend against an entity that operates with the planning, persistence, and psychological depth of a dedicated human threat actor, yet executes at machine speed and scale? That is the core challenge posed by Agentic AI. In this article, I want to walk you through why Agentic AI is the ultimate weaponizer of the human element, moving far past simple phishing into nuanced manipulation. I'll share my insights on how this technology fundamentally alters the cyber kill chain, drawing on my experience in GRC to illustrate the critical failures in our current third-party risk and operational resilience strategies. For any developer, engineer, or security professional reading this, understanding this shift isn't optional; it's the new baseline for survival. Defining the Agent: Not Your Grandfather's LLM Defining the Agent: Not Your Grandfather's LLM When most people in the industry discuss AI in the context of cyberattacks, they still envision Large Language Models (LLMs) generating contextually flawless spear-phishing emails. That's a serious threat, certainly, but it's fundamentally passive. The adversary still needs a human (or script) to manage the campaign, analyse responses, and decide the next step. Agentic AI is different. I define it as a system built around an LLM that is augmented with the ability to reason, plan, execute actions in the external digital world, and, critically, self-correct based on feedback. Think of it less as a tool and more as an autonomous software entity. The agent defines a goal, such as exfiltrating sensitive customer data, and then generates a multi-step plan: find a target, gather intelligence, probe vulnerabilities, craft an exploit, and manage the intrusion. If Step 3 fails, the agent doesn't stop; it reroutes, learns, and tries a new approach. The crucial difference I analyse in my GRC work is autonomy. An Agentic AI can spend weeks or months on continuous, silent reconnaissance, adapting its social engineering tactics in real-time until it finds the necessary weak link—and that link is almost always a human being. The New Kill Chain: Psychological Optimisation at Scale The New Kill Chain: Psychological Optimisation at Scale The traditional cyber kill chain assumes a time-consuming sequence of events, providing us with windows of opportunity to detect and mitigate. Agentic AI is shrinking these windows to near-zero. I see the most dangerous acceleration happening in the initial stages: Reconnaissance and Weaponisation. For years, I preached the importance of restricting information leakage. Now, an Agentic AI can perform the work of twenty seasoned analysts in minutes, synthesising data from social media, public records, and dark web forums. It doesn't just find an employee's name and title; it maps out their relationships, recent projects, technical language proficiency, and even their emotional state based on public posts. When it comes to social engineering, the agent optimises for psychological vulnerabilities. Traditional phishing is a spray-and-pray operation designed to catch a few low-hanging fruit. Agentic AI crafts a hyper-personalised narrative. It knows exactly which project I’m currently leading, which third-party vendor I deal with the most, and which of my colleagues I trust implicitly. It can generate communications that perfectly mimic the tone, cadence, and internal jargon of a trusted peer, leveraging my human trust to bypass layers of technical security. This capability isn't just a threat; it's a profound challenge to the very concept of the "human firewall." My Battle on the Perimeter: The Third-Party Vector My Battle on the Perimeter: The Third-Party Vector In my current role, managing third-party risk is paramount. I've always understood that my security posture is only as strong as my weakest vendor. But Agentic AI turns this common knowledge into a catastrophic event. I recently simulated an attack scenario that crystallised the danger for me. My focus was on a managed service provider (MSP) that handles our cloud environment monitoring—a trusted, long-term partner. I designed an Agentic AI to target this specific vendor, not through a mass email, but through an intricate social engineering campaign aimed at one of their junior engineers, who I knew had administrative access. The agent spent a week establishing a false digital persona. It created a highly detailed profile of a new, imaginary client contact who shared a niche technical interest with the target engineer. When the agent finally reached out, it wasn't a request for credentials; it was a complex-sounding support query related to a vulnerable partner API the MSP used. The communication was flawless: correct use of technical terminology, polite urgency, and a legitimate-looking but malicious code snippet to "debug" the supposed API issue. The engineer, trusting what he perceived as a credible peer seeking technical help on a familiar API, executed the code. What happened next was chilling: the agent automatically pivoted using the compromised credentials, established persistence, and began mapping my network, all within twenty minutes of the initial human interaction. I realised the profound shift here: the agent didn't need a vulnerability in my system to execute the breach; it exploited a vulnerability in my trust framework and the API's authentication process. My GRC framework was designed to vet the vendor's policies, not the immediate human decisions made under the duress of convincing arguments crafted by an autonomous digital predator. When Digital Meets Physical: Attacking Operational Resilience When Digital Meets Physical: Attacking Operational Resilience The most worrying aspect, from my perspective as a GRC and operational resilience specialist, is the agent's potential to coordinate multi-vector attacks that bridge the gap between IT and Operational Technology (OT). This capability moves the threat from data loss to physical disruption and potential financial paralysis. I often think about the supply chain logistics operations I've helped secure. Imagine an Agentic AI, pre-programmed with the goal of causing a major supply chain freeze for a critical manufacturing process. First, the agent executes a targeted breach into the manufacturer’s IT network (the initial domain). Once inside, it autonomously analyses the communication flow between the IT system and the OT environment, including the production scheduling servers, inventory management systems, and logistics platforms. Simultaneously, the agent initiates a secondary, unrelated social engineering campaign against a trusted third-party logistics (3PL) provider. It sends hyper-specific, time-sensitive emails to the 3PL's dispatch manager, using a tone of internal management urgency I’ve seen work countless times in crisis scenarios, compelling them to prematurely halt shipments due to a fictitious "regulatory audit." The result is a pincer movement. The agent in the IT network doesn't need to execute a destructive OT payload; it simply creates data chaos: corrupting inventory counts, adjusting production schedules by minutes, and creating phantom orders. Combined with the 3PL's genuine, human-triggered halt on shipments, the operational disruption is complete. I would have to manage not just a data breach, but a full-scale operational meltdown where the root causes are split across two trusted entities and one autonomous AI. My immediate operational resilience response would be overwhelmed by the complexity and the sheer coordination of the attack, which I could only describe as having a military-grade strategic approach. Shifting the Defence Paradigm: From Firewall to Framework Shifting the Defence Paradigm: From Firewall to Framework I believe our current obsession with technical controls, while necessary, has become secondary to the urgent need for a robust AI Governance and Risk Framework. Technical fixes are too slow to keep up with an agent that can dynamically rewrite its own exploit chain. My work in GenAI GRC has convinced me that defence must start with a radical re-evaluation of the 'human firewall' concept. We cannot train away the human capacity for error, empathy, or fatigue. Instead, I advocate for frameworks that introduce AI-powered "counter-agents" into our GRC and monitoring stacks. These counter-agents must be trained not just to detect known malicious patterns, but to identify the intent and autonomy of the adversarial agent's behaviour. I’m talking about real-time, behavioural anomaly detection on all third-party API interactions and immediate, automated policy enforcement that freezes critical processes when a human decision, however seemingly legitimate, violates a predetermined pattern of risk established by our GRC rules. This means moving authentication mechanisms away from reliance on human verification and toward zero-trust systems that scrutinise every API call and user action based on its machine-driven context, not just its human origin. The Autonomous Adversary Demands Autonomous Defence The Autonomous Adversary Demands Autonomous Defence The age of simple phishing is over. I see a future where sophisticated, autonomous Agentic AI systems are constantly probing our defences, exploiting the very human traits we value: trust, speed, and efficiency. My experience managing risk in this shifting landscape has shown me that passive defence and human training are now insufficient. The autonomous adversary demands an equally intelligent, autonomous defence. The burden of responsibility now falls on the tech community to build systems that are not just secure, but resilient by design: systems where GRC isn't an afterthought, but the core operating logic. I urge everyone building the next generation of software to embed governance and risk controls directly into the code's architecture. If we fail to do this, we are handing the keys to our digital kingdoms over to the most sophisticated, tireless, and adaptive adversaries the world has ever known. This is a challenge we can, and must, meet head-on.