CVE-2026-39885

FrontMCP is a TypeScript-first framework for the Model Context Protocol (MCP). Prior to 2.3.0, the mcp-from-openapi library uses @apidevtools/json-schema-ref-parser to dereference $ref pointers in OpenAPI specifications without configuring any URL restrictions or custom resolvers. A malicious OpenAPI specification containing $ref values pointing to internal network addresses, cloud metadata endpoints, or local files will cause the library to fetch those resources during the initialize() call. This enables Server-Side Request Forgery (SSRF) and local file read attacks when processing untrusted OpenAPI specifications. This vulnerability is fixed in 2.3.0.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/agentfront/frontmcp/releases/tag/v1.0.4	Product
https://github.com/agentfront/frontmcp/security/advisories/GHSA-v6ph-xcq9-qxxj	Exploit Vendor Advisory
https://github.com/agentfront/frontmcp/security/advisories/GHSA-v6ph-xcq9-qxxj	Exploit Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:agentfront:\@frontmcp\/adapters::::::node.js::*
	cpe:2.3:a:agentfront:\@frontmcp\/sdk::::::node.js::*
	cpe:2.3:a:agentfront:frontmcp::::::node.js::*
	cpe:2.3:a:frontmcp:mcp-from-openapi::::::node.js::*

History

No history.

Information

Published : 2026-04-08 21:17

Updated : 2026-07-24 21:10

NVD link : CVE-2026-39885

Mitre link : CVE-2026-39885

CVE.ORG link : CVE-2026-39885

JSON object : View

Products Affected

agentfront

\@frontmcp\/adapters
\@frontmcp\/sdk
frontmcp

frontmcp

mcp-from-openapi

CWE

CWE-918

Server-Side Request Forgery (SSRF)

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