{"vulnerability": "ghsa-8q49-2h5h-434x", "sightings": [{"uuid": "d1aaf40c-eb4c-4f80-83b3-b9d5bc09a97f", "vulnerability_lookup_origin": "1a89b78e-f703-45f3-bb86-59eb712668bd", "author": "9f56dd64-161d-43a6-b9c3-555944290a09", "vulnerability": "GHSA-8Q49-2H5H-434X", "type": "seen", "source": "https://gist.github.com/alon710/2148318b0f0c526c708bd7a87404909b", "content": "# GHSA-8Q49-2H5H-434X: GHSA-8Q49-2H5H-434X: Server-Side Request Forgery in FrontMCP OpenAPI Spec Poller\n\n> **CVSS Score:** 8.6\n> **Published:** 2026-07-24\n> **Full Report:** https://cvereports.com/reports/GHSA-8Q49-2H5H-434X\n\n## Summary\nA Server-Side Request Forgery (SSRF) vulnerability in FrontMCP allows unauthenticated remote attackers to query internal network services by exploiting the un-guarded background OpenAPI specification polling mechanism.\n\n## TL;DR\nThe FrontMCP background spec poller used an un-guarded global fetch() call, bypassing initial SSRF protections and allowing attackers to query internal interfaces via DNS rebinding or HTTP redirects.\n\n## Exploit Status: POC\n\n## Technical Details\n\n- **CWE ID**: CWE-918\n- **Attack Vector**: Network (AV:N)\n- **CVSS Score**: 8.6 (High)\n- **Exploit Status**: Proof of Concept\n- **KEV Status**: Not Listed\n- **Vulnerability Impact**: Server-Side Request Forgery\n\n## Affected Systems\n\n- FrontMCP\n- @frontmcp/sdk\n- @frontmcp/adapters\n- **@frontmcp/sdk**: < 1.5.6 (Fixed in: `1.5.6`)\n- **@frontmcp/adapters**: < 1.5.6 (Fixed in: `1.5.6`)\n\n## Mitigation\n\n- Upgrade FrontMCP dependency suites to v1.5.6 or higher.\n- Retain default blocked networks behavior (avoid setting allowInternalIPs to true in production configurations).\n- Restrict network communications of the runner runtime to allowlisted external domains.\n\n**Remediation Steps:**\n1. Execute dependency updates: 'npm install @frontmcp/sdk@1.5.6 @frontmcp/adapters@1.5.6'.\n2. Review application initializations to guarantee custom allowedHosts settings cover authorized specifications.\n3. Redeploy services and verify outgoing communication alerts to identify illegal internal lookups.\n\n## References\n\n- [GitHub Security Advisory GHSA-8Q49-2H5H-434X](https://github.com/advisories/GHSA-8Q49-2H5H-434X)\n- [Official Fix Commit 077201e](https://github.com/agentfront/frontmcp/commit/077201e109bf6f45dbc85c36d6bd77ded18ab13e)\n- [Pull Request #510](https://github.com/agentfront/frontmcp/pull/510)\n- [Release v1.5.6](https://github.com/agentfront/frontmcp/releases/tag/v1.5.6)\n\n\n---\n*Generated by [CVEReports](https://cvereports.com/reports/GHSA-8Q49-2H5H-434X) - Automated Vulnerability Intelligence*", "creation_timestamp": "2026-07-25T00:32:46.717663Z"}]}