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Findings

CVE-2026-39885

FrontMCP is a TypeScript-first framework for the Model Context Protocol (MCP).

Published Apr 8, 2026 · updated Jul 24, 2026 · agentfront @frontmcp/adapters

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.

Code

The project this record applies to. Exploit listings stay in References.

Timeline

Detection, updates, and resolution for this record.

  1. Apr 8, 2026 · NIST NVD

    Detected

    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 endpoi

  2. Jul 24, 2026 · NIST NVD

    Updated

    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 endpoi

Affected

  • cpe agentfront/@frontmcp/adaptersversion unspecified
  • cpe agentfront/@frontmcp/sdkversion unspecified
  • cpe agentfront/frontmcpversion unspecified
  • cpe frontmcp/mcp-from-openapiversion unspecified

Sources

  • CVE.orgVulnerability recordCVE-2026-39885

    Official CVE identifier

    cve.org
  • NIST NVDVulnerability recordCVE-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

    nvd.nist.gov

References