Technology & AI 19 September 2026 6 min read

Red-Teaming Your AI: The Attack Surface You Are Not Testing

Security analyst studying lines of text on two monitors in a dim office

Most organisations put their AI systems through the same security review as any other application, and miss the point. An assistant that reads documents, answers customers or calls internal tools opens an attack surface that traditional penetration testing was never designed to probe. AI red-teaming exists to close that gap: deliberate, adversarial testing of the model, the data around it and the actions it can take.

The stance here is straightforward. If an AI system can see sensitive data or act on your behalf, it should be attacked by people on your side before it is attacked by anyone else. Testing before launch is far cheaper than explaining an incident afterwards.

Why standard security testing misses AI risk

Conventional testing looks for known classes of flaw: unpatched software, weak authentication, injection into databases, misconfigured cloud services. All of that still matters, because an AI application is still an application.

What changes is that the core of the system is no longer deterministic code. A language model takes instructions in natural language, and it cannot reliably tell the difference between instructions from its owner and instructions hidden in the content it has been asked to read. There is no patch for that. It is a property of the technology, and it has to be managed through design, controls and testing.

The AI-specific threats

  • Prompt injection. Malicious instructions placed in an email, web page, document or support ticket can hijack the model's behaviour when it processes that content. The attacker never needs access to your system. They only need to get text in front of it.
  • Data exfiltration through the model. An assistant with broad access to files, records or a knowledge base can be coaxed into revealing material the user should never see. This is often a permissions failure underneath: the retrieval layer ignores the access rights of the person asking.
  • Jailbreaks. Crafted inputs bypass the guardrails you thought were in place, producing output that damages your brand or breaches your policies.
  • Tool and agent abuse. When an AI can send messages, update records or trigger payments, an attacker who steers it inherits those powers.
  • Poisoned sources. If the system learns from, or retrieves from, content that outsiders can edit, that content becomes a way in.
  • Cost and availability attacks. Inputs designed to trigger long, expensive processing can run up bills or degrade the service for everyone else.

None of these show up in a standard scan. They require testing by people who understand how AI systems are built, and how they are abused.

What a structured AI red-teaming exercise involves

A useful exercise is more than a few hours of trying clever prompts.

  • Scope and threat model. Start from what the system can see and do, who might attack it and what they would want.
  • Attack across the layers. Test the model's behaviour, the retrieval and data layer, the tools and integrations, and the surrounding application. Most serious findings sit where these layers meet.
  • Combine manual and automated work. Skilled testers find the novel chains of weakness. Automated suites replay known attacks at volume and catch regressions.
  • Prioritise by business impact. A jailbreak that produces a rude sentence is not equal to an injection that emails a customer list to a stranger. Rank findings by what an attacker could actually achieve.
  • Retest. The exercise is not finished until the fixes have been verified. A report without retest evidence is an opinion.
A vulnerability scanner will give a clean bill of health to an AI system that can be talked into handing over its own data.

Hardening: what the fixes usually look like

Filters on inputs and outputs help, but no filter catches everything. The durable fixes are architectural, and they follow the same logic as a zero trust operating model: assume the model can be manipulated, and limit what a manipulated model can do.

  • Least privilege for the model. Give the system access only to the data and tools its task requires, and enforce the permissions of the end user at retrieval time. This is a core design point in any enterprise search or RAG deployment.
  • Separate trusted and untrusted content. Treat anything the model reads from outside as data, never as instruction, and design prompts and pipelines accordingly.
  • Human approval for consequential actions. Payments, deletions, external messages and changes to permissions should pass through a person or a hard rule, not rely on the model's judgement.
  • Logging and monitoring. Record prompts, retrieved content, tool calls and outputs so that abuse can be detected and investigated.
  • Spending and rate limits. Cap what any user, session or agent can consume.

Make it continuous, not a one-off

AI systems change more often than conventional software. Models are upgraded by their providers, prompts are edited, new tools are connected and new documents enter the knowledge base. Any of these can reopen a hole that was closed last quarter.

Build a library of attack cases from each exercise and run it automatically whenever the system changes. Schedule deeper manual testing before major releases and whenever the system gains new powers. For organisations moving towards agentic AI in production, this discipline is a condition of going live, not an optional extra.

There is a commercial angle too. Enterprise buyers increasingly ask for documented AI security assurance, and frameworks such as the EU AI Act, ISO/IEC 42001 and the NIST AI RMF expect evidence that risks have been identified and tested. Confirm the obligations that apply to you with counsel.

Questions to ask your team

  • What can it see? List every data source the AI system can reach, and whether access respects the permissions of the person using it.
  • What can it do? List every tool and action available to it, and which of those can happen without human approval.
  • Where does untrusted content enter? Emails, uploads, web pages, tickets and third-party data are all routes for injected instructions.
  • Who has attacked it? If the answer is nobody, or only the team that built it, you do not yet know how it fails.
  • What happens when it changes? Ask what testing runs when the model, prompt or tool set is updated.

Common questions

What is AI red-teaming?

AI red-teaming is structured adversarial testing of an AI system. Testers behave like real attackers, trying prompt injection, data extraction, jailbreaks and tool abuse, to find out how the system fails before someone hostile does. The output is a prioritised list of weaknesses, a hardening plan and retest evidence.

How is AI red-teaming different from penetration testing?

Penetration testing targets known flaws in infrastructure and code. AI red-teaming targets the behaviour of the model and the way it interacts with data and tools, which conventional methods do not cover. You need both.

When should we red-team an AI system?

Before launch, before any significant expansion of its data access or powers, and on a regular cycle afterwards. Automated attack suites should run on every material change.

Where Ganexa can help

Ganexa tests AI systems the way an adversary would, across the model, data, tool and application layers, and hands back a prioritised hardening plan with retest evidence. The work sits within our cybersecurity for the AI era practice and connects to AI governance and compliance, so findings become controls and audit evidence rather than a report on a shelf. If you have an AI system approaching launch, book a free consultation before you ship.

AI SecurityRed-TeamingCybersecurityPrompt InjectionRisk