Design of a Security Framework for Multi-Agent Systems Based on Model Context Protocol in SOC Environments

Security Operations Centers (SOCs) rely on Level 1 analysts to triage increasing alert volumes amid alert fatigue and tool fragmentation. LLM-based multi-agent systems using the Model Context Protocol (MCP) are being adopted to automate these tasks, but their autonomy and tool access expose them to attacks such as tool poisoning, indirect prompt injection, and confused deputy exploitation. To address this gap, this work proposes a security framework for MCP-based multi-agent SOC pipelines, implemented as a middleware layer comprising a tool registration validator and five execution layers: access control, rate limiting, input validation, output validation, and audit logging. The framework is applied to a triage-enrichment-response pipeline connected to a Wazuh SIEM through a custom MCP server. Of the 35 attack vectors considered in a threat model derived from different threat taxonomies, including OWASP, MITRE ATLAS, and ATFAA, 29 are addressable at the middleware level and are covered by the framework’s controls. These controls are then validated experimentally using a purpose-built malicious MCP server and targeted test-harness injections, organized into six test suites that together exercise the covered vectors across 600 executions. Every attack instance in the evaluated threat model was blocked, none bypassed the framework, and no legitimate call in the evaluated set was incorrectly rejected; obfuscated variants, however, evade the lexical content-inspection controls, delimiting the scope of this result. A full-pipeline demonstration confirms that the framework preserves benign operational outputs. These results indicate that systematic middleware controls can secure MCP-based agentic SOC deployments without modifying the underlying agents or MCP servers.