CVE-2026-39885
FrontMCP Affected by SSRF via $ref Dereferencing in Untrusted OpenAPI Specifications
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.
| CWE | CWE-918 |
| Vendor | agentfront |
| Product | frontmcp |
| Published | Apr 8, 2026 |
| Last Updated | Apr 9, 2026 |
Get instant alerts for agentfront frontmcp
Be the first to know when new high vulnerabilities affecting agentfront frontmcp are published — delivered to Slack, Telegram or Discord.
CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N