AI & LLM Penetration Testing
LLMs are being integrated into products, workflows, and customer-facing systems faster than anyone is testing them. A single prompt injection flaw can turn your AI feature into a data exfiltration tool.
What is AI & LLM Penetration Testing?
Security assessment of AI-powered applications and large language model (LLM) integrations — testing for prompt injection, model manipulation, data leakage, and AI-specific attack vectors.
Most AI and LLM deployments are in production before anyone has assessed what an attacker could extract, manipulate, or exploit. Prompt injection, data leakage, and model manipulation are real, exploitable risks — and the attack surface is new enough that most security teams have limited experience assessing it.
At a Glance
- Frameworks
- OWASP LLM Top 10, NIST AI RMF
- Typical Timeline
- 3–7 days depending on system complexity
- Report
- Executive summary + full technical findings
- Retest
- Complimentary, included in every engagement
- NDA
- Signed before any technical discussion
Outcomes that move your security forward
What You Receive
Executive Summary Report
AI/LLM risk overview for product, security, and leadership teams
Full Technical Report
All findings mapped to the OWASP LLM Top 10 with proof-of-concept prompts and reproduction steps
Prompt Injection Test Results
Documented adversarial prompt attempts and their outcomes
Integration Security Assessment
Review of API integration security, input validation, and output handling
Developer Remediation Guide
Practical mitigations including prompt hardening and architectural recommendations
Retest Report
Confirms mitigations are effective after your team applies fixes
What We Test
How We Run This Engagement
Every engagement follows a defined, transparent process — no surprises, no hidden scope changes, and no invoice for work you did not agree to.
Scoping
Understand the AI system architecture, LLM provider, integration points, and threat model.
Prompt Engineering & Injection Testing
Systematically attempt to manipulate LLM behaviour through adversarial prompts.
API & Integration Testing
Test the security of the surrounding application and API layer.
Data Leakage & Privacy Testing
Assess whether the model can be made to reveal training data or sensitive information.
Reporting
Findings mapped to OWASP LLM Top 10 with remediation guidance.
Retest
Verify mitigations are effective.
Why Work With Vigilant Defenders
Manual Testing. Not Scanner Output.
Automated tools find known signatures. Our certified consultants find the chained attack paths, logic flaws, and context-specific vulnerabilities that no scanner will surface. Every finding we report is manually verified — zero false positives.
Reports Built for Action, Not Filing.
Every finding includes a proof-of-concept, a CVSS risk score, the affected system or endpoint, and step-by-step remediation guidance written for the team that has to fix it. Your developers and your board both get a report they can use.
Confidentiality From Day One.
We sign a formal NDA before any technical discussion begins. Your vulnerabilities, your architecture, and your engagement findings are treated with the same confidentiality as attorney-client communications. We have never disclosed client information.
We Stay Until It's Fixed.
Every engagement includes a complimentary retest once your team has addressed the findings. We verify that the vulnerabilities are genuinely closed — not surface-patched — and issue a formal retest certificate you can share with clients and auditors.
We Work at the Frontier of AI Security.
AI security testing is not just a renamed web app checklist. We have hands-on experience with LLM integrations, RAG pipelines, and agentic AI systems — and we follow the rapidly evolving OWASP LLM Top 10 and NIST AI Risk Management Framework to ensure your AI deployment is assessed against the latest known threats.
Frequently asked questions
Everything you need to know about this engagement.
LLMs are being integrated into customer-facing products, internal tools, and automated workflows at speed — often without security review. Prompt injection alone can lead to data exfiltration, unauthorised actions, and reputational damage.
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Find Out How Your AI Integration Can Be Exploited
Get a free scoping consultation — no commitment required. We’ll scope the right AI & LLM penetration testing engagement for your environment and send a fixed-fee proposal within 24 hours.