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.
Affected products
agentfront: \@frontmcp\/adapters; agentfront: \@frontmcp\/sdk; agentfront: frontmcp; frontmcp: mcp-from-openapi
References3
- github.com/agentfront/frontmcp/security/advisories/GHSA-v6ph-xc… ExploitVendor Advisory
- github.com/agentfront/frontmcp/security/advisories/GHSA-v6ph-xc… ExploitVendor Advisory
- github.com/agentfront/frontmcp/releases/tag/v1.0.4 Product
Metrics
- CVSS 3.1
-
7.5
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N - EPSS — exploit probability
- 0% percentile: 35 · as of 12 November 2026
- CWE
- CWE-918
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