CVE-2026-39885
Published: Apr 8, 2026
Modified: Apr 9, 2026
CVSS v3.1
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.
| Vendor | Product | Versions |
|---|---|---|
agentfront | frontmcp | affected < 1.0.4 |
@frontmcp | adapters | affected < 1.0.4 |
@frontmcp | sdk | affected < 1.0.4 |
frontmcp | mcp-from-openapi | affected < 2.3.0 |
Weaknesses (CWE)
CVSS v3.1 Details
CVSS v3.1 Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
Attack Vector
Attack Complexity
Privileges Required
User Interaction
Scope
Confidentiality
Integrity
Availability
References
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