This article was originally published on AI Study Room . For the full version with working code examples and related articles, visit the original post. Prompt Injection Prevention: Securing Your LLM Applications (2026) Prompt injection is the #1 security risk for LLM applications in 2026, ranked as OWASP LLM01. An attacker who can inject instructions into your LLM can exfiltrate data, bypass safety controls, or execute unauthorized actions. Every LLM application that processes untrusted input — which is almost all of them — needs defenses. This guide covers attack patterns and practical defenses you can implement today.…