{"id":"CVE-2026-39885","summary":"FrontMCP Affected by SSRF via $ref Dereferencing in Untrusted OpenAPI Specifications","details":"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.","aliases":["GHSA-v6ph-xcq9-qxxj"],"modified":"2026-07-08T08:13:05.087917277Z","published":"2026-04-08T20:34:20.538Z","database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/39xxx/CVE-2026-39885.json","unresolved_ranges":[{"source":"AFFECTED_FIELD","extracted_events":[{"fixed":"2.3.0"}]}],"cwe_ids":["CWE-918"],"cna_assigner":"GitHub_M"},"references":[{"type":"WEB","url":"https://github.com/agentfront/frontmcp/releases/tag/v1.0.4"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/39xxx/CVE-2026-39885.json"},{"type":"ADVISORY","url":"https://github.com/agentfront/frontmcp/security/advisories/GHSA-v6ph-xcq9-qxxj"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-39885"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/agentfront/frontmcp","events":[{"introduced":"0"},{"fixed":"c13e7651968d08223bcf996d4d39f84fe2040c4c"}],"database_specific":{"source":["AFFECTED_FIELD","CPE_RANGE","REFERENCES"],"cpe":["cpe:2.3:a:agentfront:\\@frontmcp\\/adapters:*:*:*:*:*:node.js:*:*","cpe:2.3:a:agentfront:\\@frontmcp\\/sdk:*:*:*:*:*:node.js:*:*","cpe:2.3:a:agentfront:frontmcp:*:*:*:*:*:node.js:*:*"],"extracted_events":[{"introduced":"0"},{"fixed":"1.0.4"}]}}],"versions":["v1.0.3","v1.0.2","v1.0.1","v1.0.0","v1.0.0-rc.1","v1.0.0-beta.14","v1.0.0-beta.13","v1.0.0-beta.12","v1.0.0-beta.11","v1.0.0-beta.10","v1.0.0-beta.9","v1.0.0-beta.8","v1.0.0-beta.7","v1.0.0-beta.6","v1.0.0-beta.5","v1.0.0-beta.4","v1.0.0-beta.3","v1.0.0-beta.2","v1.0.0-beta.1","v0.8.1","v0.8.0","v0.7.2","v0.7.1","v0.6.3","v0.6.2","v0.6.1","v0.6.0","v0.5.1","v0.5.0","v0.4.0","v0.3.1","v0.3.0","v0.2.5"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-39885.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N"}]}