23 Oct 2026 15:48:27 UTC
MaxKB: Known MCP tool IDs expose owner Tool.code and can be referenced by attacker workflows
cve-program · CVE-2026-77518 · Published
CVE-2026-77518
MaxKB: Known MCP tool IDs expose owner Tool.code and can be referenced by attacker workflows
CVSS 3.1 5.0 MEDIUMCheck source for fixed versionsKEV status unknown
cve-program · CVE-2026-77518
PublishedMaxKB is an open-source AI assistant for enterprise. In 2.10.2-lts and earlier, a normal workspace user who knows another user's active MCP tool_id in the same workspace can retrieve the hidden tool through the tool-detail route because it does not apply the per-resource authorization used by the list route. The response includes Tool.code, which may contain MCP server configuration and headers, and an attacker who can create or edit an attacker-owned workflow can place the same foreign mcp_tool_id in a workflow mcp-node so workflow debug uses the owner's MCP configuration without verifying permission to use that tool. No fixed version is available as of this review.
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