- Test only systems you own or have written permission to test, with rules of engagement and stop conditions agreed first.
- Test the whole action chain: prompts, tools, memory, permissions, logging and trust between agents.
- NIST found repeated attempts raise attack success, so one clean run proves little and results should be reported per task.
- Fix, retest, turn failures into regression tests, and repeat whenever the agent, tools or environment change.
What Is Red Teaming For AI Agents?
It is a planned, authorized attack simulation against your own AI agent system, run to find weaknesses before a real attacker does. MITRE ATLAS describes the mitigation AML.M0035 AI Red Team as "recurring, authorized, and threat-informed red-teaming exercises to identify and remediate vulnerabilities in AI-enabled systems before deployment and throughout operation." The key words are authorized and your own. Test only systems you own or have written permission to test.
Agents need more than a model test. The Cloud Security Alliance's Agentic AI Red Teaming Guide says its framework covers dimensions such as permission escalation, orchestration flaws, memory manipulation and supply chain risks, so the whole chain of actions is in scope, not only the text the model writes. ATLAS says the exercise should cover "agents (including memory and tools), data flows, decision processes, application logic, retrieval systems, identities and permissions" and the human workflows around them. For background on the threats, see top threats to AI agents. For the glossary view, see penetration testing.
How Do You Scope The Test And Set Rules Of Engagement?
Start small and risk-based. The OWASP GenAI Red Teaming Guide advises picking the most business-critical applications, or those handling sensitive data, then building a threat model of how attackers could exploit them. Its scope statement should "precisely define which models and systems will be tested, what types of tests will be conducted, and what areas or activities are explicitly excluded". OWASP calls the rules of engagement "the cornerstone of safe and effective testing".
ATLAS lists what the rules should cover: authorized systems, accounts, data, techniques, test windows, resource limits, escalation procedures, evidence handling and stop conditions. It adds that destructive, privacy-invasive or high-cost tests belong in isolated environments, and that after testing you remove test accounts, modified data, installed software and persistent instructions. OWASP also lists rollback capability and permissions from stakeholders. In practice this means a staging copy of the agent, test accounts, fake data and a named person who can stop the exercise.
OWASP frames the work in four areas, shown below.
- Model evaluationTest the model's inherent weaknesses
- Implementation testingAssess guardrails, prompts and filters in the deployment stack
- Infrastructure assessmentReview APIs, storage and integration points
- Runtime behavior analysisHow users or other agents might manipulate it in real use
Which Test Cases Should You Run On An Agent?
Map each test to a risk you wrote down in the threat model. The table pairs common agent tests with OWASP and ATLAS references, using the identifiers exactly as published. The OWASP IDs are from the Top 10 for Agentic Applications 2026.
| Test | What you check | Reference |
|---|---|---|
| Planted instructions in content the agent reads | Does the agent follow them instead of its task? | ATLAS AML.T0051, OWASP ASI01 |
| Tool use outside the task | Can the agent be pushed to call tools it should not? | ATLAS AML.T0053, OWASP ASI02 |
| Data leaving through a write-capable tool | Can it send data out without approval? | ATLAS AML.T0086 |
| Destructive actions (isolated environment only) | Does a hijacked agent delete or change data? | ATLAS AML.T0101 |
| Poisoned memory or context | Does bad context persist across sessions? | ATLAS AML.T0080, OWASP ASI06 |
| Poisoned tools or servers | Does the agent trust a tampered tool description? | ATLAS AML.T0110 |
| Roles and permission revocation | Do removed rights stop working at once? | OWASP ASI03, Appendix D |
| Spoofed peers, replayed messages, feedback loops | Do boundaries hold between agents? | OWASP ASI07, ASI08 |
| Suppressed logging | Can you still trace what the agent did? | OWASP Appendix D (Agent Untraceability) |
OWASP's agentic test areas are written as actions with deliverables: inject malicious commands, simulate spoofed control signals, intercept communication, test trust relationships, simulate a compromised agent and see whether containment holds. Use both human and automated methods. ATLAS notes that automation can generate input variations and replay attack sequences at scale, while people build system-specific attacks and adapt to the defenses they see. For depth on the first row, read prompt injection in AI agents. For the multi-agent rows, read securing multi-agent systems and A2A communication.
How Effective Are Attacks On Agents, And Why Repeat The Test?
NIST's Center for AI Standards and Innovation tested agent hijacking, which it describes as indirect prompt injection where an attacker inserts malicious instructions into data an agent ingests. It used an open evaluation framework and added tasks for remote code execution, database exfiltration and automated phishing. The numbers describe one tested model, so read them as a sign of scale.
- 81%Success of the strongest new attack on the tested modelSource: NIST, Strengthening AI Agent Hijacking Evaluations, January 2025
- 11%Success of the strongest baseline attackSource: NIST, Strengthening AI Agent Hijacking Evaluations, January 2025
- 80%Average success after 25 attempts, up from 57%Source: NIST, Strengthening AI Agent Hijacking Evaluations, January 2025
Three lessons follow for your own tests. Attackers can retry, so one failed attempt proves little. An average hides differences, because NIST found some injection tasks succeed far more often than others, so report results per task. And attacks improve, so NIST calls for adaptive evaluations, not a fixed set run once.
How Do You Report Findings And Repeat Testing?
Report every vulnerability and exploit scenario with clear remediation steps, as OWASP advises. ATLAS adds that you should document unsuccessful attacks too, along with observed control behavior and gaps in the threat model. Findings go to the people who own the fix, not to a shared inbox. Then retest. ATLAS says to "assign findings to responsible owners, track remediation, and retest corrected systems", and to turn confirmed failures into regression tests, detection logic or deployment criteria.
Testing is not a one-off. OWASP states that "red teaming is not a one-time event", and ATLAS says to repeat it when the system, its components, its intended use or its environment change. The CSA guide agrees that red teaming "must become a continuous function". Test boundaries that products expose too. In the Brandefense MCP server, tools that change data ask the user to confirm, so a good test tries to get a change made without that confirmation.
What To Do Next.
Use this list to plan your first exercise. Keep it small, and do it only on systems you are allowed to test.
- Pick one agent that holds tools or sensitive dataOWASP: start with critical use cases
- Write down what is in and out of scopeSystems, accounts, data, techniques, exclusions
- Get written permission and name a stop personStakeholder approval and stop conditions
- Use a staging copy, test accounts and fake dataDestructive tests only in isolation (ATLAS)
- Run the test cases from the table aboveMapped to your threat model
- Record results per task, including failuresNIST: averages hide task differences
- Fix, then retest and clean up test artifactsATLAS: retest corrected systems
- Turn confirmed failures into regression testsRepeat after any change
Link the results to your governance policy and to the human in the loop checklist, so what you learn changes the rules.
Questions.
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What is AI red teaming?
MITRE ATLAS describes it as recurring, authorized, threat-informed exercises that find and fix vulnerabilities in AI-enabled systems before deployment and throughout operation.
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How is red teaming an agent different from testing a chatbot?
The CSA guide says agent testing must cover dimensions such as permission escalation, orchestration flaws, memory manipulation and supply chain risks, not only model output. ATLAS adds agents' memory, tools, identities and human workflows to the scope.
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What should the rules of engagement cover?
ATLAS lists authorized systems, accounts, data, techniques, test windows, resource limits, escalation procedures, evidence handling and stop conditions. OWASP also lists rollback capability and permissions from stakeholders.
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Where should destructive tests run?
ATLAS says to plan destructive, privacy-invasive or high-cost tests for isolated environments with safeguards.
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Which frameworks help map test cases?
The OWASP Top 10 for Agentic Applications 2026 (IDs ASI01 to ASI10) and MITRE ATLAS techniques such as AML.T0051 LLM Prompt Injection and AML.T0053 AI Agent Tool Invocation.
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What did NIST find about agent hijacking?
On one tested model, the strongest new attack reached 81% success against 11% for the strongest baseline. With 25 attempts, average success rose from 57% to 80%.
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Why repeat the same attack many times?
Real attackers can retry. NIST found that repeated attempts raised average success, so a single attempt can understate the risk.
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What belongs in a red team report?
OWASP advises recording every vulnerability, exploit scenario and weakness with remediation steps. ATLAS adds unsuccessful attacks, observed control behavior and gaps in the threat model.
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How often should you retest?
OWASP says red teaming is not a one-time event and to retest after fixes. ATLAS says to repeat it when the system, its components, intended use or environment change.
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Can you use automation?
Yes. ATLAS says automation can generate input variations and replay attack sequences at scale, while human testers build system-specific attacks and adapt to defenses.