Prompt Injection Attacks

Hey,

Hope you're keeping well.

A prompt injection attack occurs when a malicious user crafts input that manipulates an AI system’s instructions, causing it to override intended behavior and potentially access or leak sensitive data. In practice, this can happen in LLM-powered .NET or ASP.NET applications when untrusted user text is passed directly into prompts without sanitization, similar to SQL injection but targeting the model’s logic layer. Real-world cases include attackers embedding hidden instructions in user content that force the AI to reveal confidential information or execute unintended API calls. In .NET solutions, mitigation involves strict input validation, context isolation, and using Azure AI Content Safety or custom middleware to inspect and sanitize prompts before they reach the model. Treat prompts as code execution surfaces and apply the same secure coding and DevOps review practices you would for any external input.

Thanks and regards,

Taz