Prompt Injection Attacks Explained | LLM Penetration Testing (OWASP LLM01)

Can a hidden instruction inside a resume, PDF, webpage, or AI agent memory manipulate your LLM application?

Prompt injection is one of the most serious security risks facing AI-powered applications. A single malicious instruction hidden in untrusted content can influence AI decisions, expose sensitive information, or trigger unauthorized actions.

In Episode 1 of VISTA InfoSec's 10-part LLM Penetration Testing series, Avinash Sharma explains OWASP LLM01: Prompt Injection, how these attacks work, and how organizations can test and secure their AI applications.

🔍 What You'll Learn:

✅ What prompt injection is and why it matters for LLM security

✅ Direct vs. indirect prompt injection attacks

✅ How malicious instructions enter AI applications through documents, webpages, emails, and tools

✅ Real-world-style attack scenarios involving AI recruitment, data exfiltration, and persistent memory

✅ How AI agent permissions increase the impact of prompt injection

✅ Black-box and white-box LLM penetration testing techniques

✅ Practical mitigation strategies, authorization controls, and continuous security testing

🛡️ Is Your AI Application Vulnerable to Prompt Injection?

AI-powered applications need more than prompt filtering. Organizations should assess how untrusted content interacts with LLM instructions, connected tools, sensitive data, and automated workflows.

VISTA InfoSec provides security assessments for AI applications, including testing for prompt injection, insecure integrations, excessive permissions, and potential data exposure.

00:00 Introduction: Hidden Prompt Injection in a Resume
[MM:SS] What Is Prompt Injection?
[MM:SS] Prompt Injection vs. Jailbreaking
[MM:SS] How Indirect Prompt Injection Works
[MM:SS] Where Malicious Instructions Enter LLM Applications
[MM:SS] Business Impact and AI Agent Risk
[MM:SS] Scenario 1: The Resume That Hires Itself
[MM:SS] Scenario 2: Data Exfiltration Through Markdown
[MM:SS] Scenario 3: Persistent AI Memory Injection
[MM:SS] How to Test for Prompt Injection Vulnerabilities
[MM:SS] Prompt Injection Prevention and Mitigation
[MM:SS] VISTA InfoSec's LLM Security Testing Approach
[MM:SS] Four Key Takeaways and Next Episode

👉 Discuss an LLM Security Assessment with VISTA InfoSec:
https://vistainfosec.com/contact-us/

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📚 About This Series

This is Episode 1 of our 10-part OWASP Top 10 for LLM Applications security series.

Each episode explores a major LLM application vulnerability, attack scenarios, business impact, penetration testing approaches, and practical security controls.

🔔 Subscribe to VISTA InfoSec for more videos on AI security, LLM penetration testing, cybersecurity assessments, and regulatory compliance.

💬 Join the Discussion

Which is the biggest prompt injection risk in your organization: untrusted documents, AI agent tool access, or persistent memory?

Share your thoughts in the comments.