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1 vulnerability by frontmcp

CVE-2026-39885 (GCVE-0-2026-39885)

Vulnerability from cvelistv5 – Published: 2026-04-08 20:34 – Updated: 2026-04-09 16:16
VLAI?
Title
FrontMCP Affected by SSRF via $ref Dereferencing in Untrusted OpenAPI Specifications
Summary
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.
Severity ?
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
CWE
  • CWE-918 - Server-Side Request Forgery (SSRF)
Assigner
References
Impacted products
Vendor Product Version
agentfront frontmcp Affected: < 1.0.4
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