FKIE_CVE-2026-39885

Vulnerability from fkie_nvd - Published: 2026-04-08 21:17 - Updated: 2026-04-15 19:04
Severity ?
7.5 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
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.
References
security-advisories@github.comhttps://github.com/agentfront/frontmcp/releases/tag/v1.0.4Product
security-advisories@github.comhttps://github.com/agentfront/frontmcp/security/advisories/GHSA-v6ph-xcq9-qxxjExploit, Vendor Advisory
134c704f-9b21-4f2e-91b3-4a467353bcc0https://github.com/agentfront/frontmcp/security/advisories/GHSA-v6ph-xcq9-qxxjExploit, Vendor Advisory
Impacted products
Vendor Product Version
agentfront \@frontmcp\/adapters *
agentfront \@frontmcp\/sdk *
agentfront frontmcp *
frontmcp mcp-from-openapi *
To clipboard 

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  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "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."
    }
  ],
  "id": "CVE-2026-39885",
  "lastModified": "2026-04-15T19:04:51.807",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "NONE",
          "baseScore": 7.5,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "NONE",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N",
          "version": "3.1"
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        "impactScore": 3.6,
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        "type": "Secondary"
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  },
  "published": "2026-04-08T21:17:00.833",
  "references": [
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      "tags": [
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  "vulnStatus": "Analyzed",
  "weaknesses": [
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          "value": "CWE-918"
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      "source": "security-advisories@github.com",
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}


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