An issue was discovered in mcp-neo4j 0.3.0 allowing attackers to obtain sensitive information or execute arbitrary commands via the SSE service.
Date: 2025-09
Attack vector: info-disclosure
Category: vulnerability-disclosure
Severity: High
CVE: CVE-2025-56406
CWE: CWE-200
CWE-284
CWE-77
CVSS: 7.5 (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N)

An issue was discovered in mcp-neo4j 0.3.0 allowing attackers to obtain sensitive information or execute arbitrary commands via the SSE service. NOTE: the Supplier's position is that authentication is not mandatory for MCP servers, and the mcp-neo4j MCP server is only intended for use in a local environment where authentication realistically would not be needed. Also, the Supplier provides middleware to help isolate the MCP server from external access (if needed).


Mitigations:

Architectural layers (MAESTRO):