Analysis of the Architecture of an Agentic LLM-Based Cybersecurity Incident Response System

This article provides an in-depth analysis of an open-source agent-driven LLM cybersecurity incident response project. Addressing challenges faced by traditional Security Operations Centers (SOCs) such as handling massive alerts, analyst fatigue, and response delays, it designs an eight-phase architecture with core modules including email parsing, CoT reasoning, memory system, RAG enhancement, and MCP tool integration. It also achieves continuous learning optimization through a self-feedback mechanism, aiming to improve the efficiency and accuracy of security operations.

Cybersecurity incident response is a key component of an enterprise's security system. While traditional SIEM systems can collect and correlate logs, they heavily rely on human experts for alert analysis, threat classification, and generation of disposal recommendations. The core objective of this project is to build an agent system based on large language models that can automatically parse security incidents, identify attack patterns, classify threats, and generate structured mitigation recommendations. By combining LLM reasoning capabilities with security expertise, it aims to achieve end-to-end automation from alert reception to disposal execution.

The system adopts a phased pipeline design with the following flow: SIEM alert (email) → Phase1 Email Parser → Structured JSON → Phase2 CoT Agent → Phase3 Memory System (Redis + MySQL) → Phase4 Feedback Loop + Self-Optimization → Phase5 RAG Integration (LangChain) → Phase6 MCP Server Integration → Phase7 CoT + ReAct Agent → Phase8 Testing and Validation. The modular design supports independent development and optimization, with core modules including email parsing for standardized data, CoT reasoning engine, dual-layer memory system, RAG knowledge enhancement, and MCP tool connector.

1. Email Parsing and Standardization: Extract key fields such as alert_type, severity, source_ip, and output structured JSON;
2. CoT Analysis Engine: Adopt an observation→thinking→suggestion reasoning process, combine the MITRE ATT&CK framework and CVE database, and ensure output consistency through few-shot learning;
3. Dual-Layer Memory System: Short-term memory (Redis) stores recent decisions, while long-term memory (MySQL) stores historical events, supporting context awareness and trend analysis;
4. Self-Feedback Optimization: The agent self-reviews recommendations, identifies issues, stores feedback, and continuously improves decision-making;
5. RAG Knowledge Enhancement: Integrate MITRE ATT&CK, CVE, and historical alert patterns based on LangChain to enhance recommendation accuracy;
6. MCP Tool Integration: Interact with tools such as firewalls, ticketing systems, and EDR through standardized interfaces to execute operations like block_ip and create_ticket;
7. ReAct Agent: Combine reasoning and action, execute response operations, and monitor results to adjust strategies.

The project ensures reliability through virtual machine-simulated attack scenarios and SIEM integration testing. Key performance metrics monitored include: recommendation accuracy (target manual approval rate >80%), response time (target <5 seconds from alert to recommendation), and learning rate (accuracy curve improving over time).

This system can alleviate analyst fatigue (by automating low-level alerts), shorten response time (from hours to seconds), accumulate expert knowledge, and continuously adapt to new attack methods. As LLM capabilities improve and security data accumulates, agentic systems are expected to become standard configurations for SOC operations, driving cybersecurity defense into a new era of intelligence.