A comprehensive guide to offensive and defensive security for Large Language Models and Agentic AI Systems, updated for February 2026 with the OWASP Top 10 for LLMs 2025, corrected OWASP Top 10 for Agentic Applications 2026 (ASI prefix), new security tools, recent incidents, and AI regulation coverage.
Overview • What's New • Quick Start • OWASP LLM 2025 • 🆕 OWASP Agentic 2026 • Tools • Resources
⚡ MAJOR UPDATE: This guide has been significantly updated with critical corrections and new content for 2026. The OWASP Agentic Top 10 identifiers have been corrected from the unofficial "AAI" prefix to the official "ASI" (Agentic Security Issue) prefix with proper ordering per the December 2025 release. New sections cover DeepSeek R1 security concerns, recent AI security incidents, emerging red teaming tools, and AI regulations.
This guide covers the OWASP Top 10 for LLM Applications 2025 (released November 18, 2024) and the OWASP Top 10 for Agentic Applications 2026 (released December 10, 2025). Key topics include Agentic AI Security, RAG Vulnerabilities, System Prompt Leakage, Vector/Embedding Weaknesses, and AI Compliance.
As Large Language Models become the backbone of enterprise applications, from customer service chatbots to code generation assistants, the security implications have evolved dramatically. This guide provides a comprehensive resource for:
The November 2024 release introduced significant changes reflecting real-world AI deployment patterns: