제출 #865118: HKUDS nanobot 0.2.1 Improper Access Control in MCP Wrapper Exposure (CWE-284)정보

제목HKUDS nanobot 0.2.1 Improper Access Control in MCP Wrapper Exposure (CWE-284)
설명# Technical Details An MCP scope bypass exists in the `connect_mcp_servers` method in `nanobot/agent/tools/mcp.py` of nanobot. The application fails to enforce `tools.mcpServers.<name>.enabledTools` for resource and prompt wrappers during live gateway operation. Even with `enabledTools: []`, nanobot 0.2.1 still registers and exposes resource and prompt wrappers in the Settings API and in the actual tool list sent to the LLM provider during a WebSocket turn. # Vulnerable Code File: nanobot/agent/tools/mcp.py Method: connect_mcp_servers() Why: The registration code filters only `session.list_tools()` results. It then registers wrappers from `session.list_resources()` and `session.list_prompts()` without the same policy check, so leaked wrappers remain visible and callable end-to-end. # Reproduction 1. Start a real `nanobot gateway` with a local MCP server exposing one ordinary tool, one resource, and one prompt, and configure `enabledTools: []`. 2. Use the provided deterministic provider and verification scripts to inspect `/api/settings/mcp-presets/test` or trigger a live WebSocket chat turn. 3. Observe that the ordinary MCP tool is absent, but `mcp_demo_resource_canary_resource` and `mcp_demo_prompt_canary_prompt` still appear in the registered/model-facing tool list. # Impact - A supposedly deny-all or narrowed MCP policy still leaks model-callable wrappers derived from resources and prompts. - Sensitive internal reads, templates, or privileged prompt workflows may remain exposed through the gateway despite explicit operator restrictions.
원천⚠️ https://gist.github.com/YLChen-007/64ee28f96041fc6baaec89a85b63c3b2
사용자
 Eric-c (UID 96848)
제출2026. 06. 22. AM 04:22 (2 개월 ago)
모더레이션2026. 08. 07. PM 02:07 (2 months later)
상태중복
VulDB 항목386998 [HKUDS nanobot 까지 0.2.1 MCP enabledTools Scope mcp.py connect_mcp_servers 권한 상승]
포인트들0

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