CVE-2026-39885

HIGH

7.5

Description

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.

CVE Details

CVSS v3.1 Score7.5

SeverityHIGH

CVSS VectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

Attack VectorNETWORK

ComplexityLOW

Privileges RequiredNONE

User InteractionNONE

Published4/8/2026

Last Modified4/15/2026

Sourcenvd

Honeypot Sightings0

Affected Products

agentfront:\@frontmcp\/adaptersagentfront:\@frontmcp\/sdkagentfront:frontmcpfrontmcp:mcp-from-openapi

Weaknesses (CWE)

CWE-918

References

https://github.com/agentfront/frontmcp/releases/tag/v1.0.4(security-advisories@github.com)

https://github.com/agentfront/frontmcp/security/advisories/GHSA-v6ph-xcq9-qxxj(security-advisories@github.com)

https://github.com/agentfront/frontmcp/security/advisories/GHSA-v6ph-xcq9-qxxj(134c704f-9b21-4f2e-91b3-4a467353bcc0)

IOC Correlations

No correlations recorded

This product uses data from the NVD API but is not endorsed or certified by the NVD.