CVE-2026-67531: FrontMCP Sandbox Escape Leading to RCE
FrontMCP
A sandbox escape vulnerability in FrontMCP enables scripts to leverage Proxy invariants and access the host Function constructor. This allows remote code execution in the server process via tool calls.
disclosed CVENo confirmed exploitation, so this record is tracked as a disclosed vulnerability and not counted as an incident. It moves into the counts if CISA or the vendor confirms exploitation. Why
- CVSS
- 9.3
- EPSS
- 0.01 · top 45% · 2026-11-13
- fix status
- Fix status unknown
- first report
- 6 Aug 2026
- last update
- 6 Aug 2026
- CVE ids
Timeline · 1
Sources · 1
Advisories and databases
- 2026-08-06CVE-2026-67531: FrontMCP is a TypeScript-first framework for the Model Context Protocol (MCP).NVD · nvd.nist.gov/vuln/detail/CVE-2026-67531
Titles and links belong to their publishers. The summary above is written by gcdRadar in its own words; data is CC BY-SA 4.0.
Classification
- lane
- Patch now
- AI role
- Attack on AI
- categories
- Infrastructure vulnerability
- severity
- 2 · Disclosed vulnerability
- fix status
- Fix status unknown
- targets
- Framework / tooling
- owasp llm top 10
- LLM03:2025 Supply Chain
- mitre atlas
- no technique for these categories
- dates
- happened 6 Aug 2026 · first reported 6 Aug 2026
- origin
- NVDVulnerability record from NVD / the GitHub Advisory Database. This product uses the NVD API but is not endorsed or certified by the NVD.
- record
- confidence 0.95 · created 2026-10-18 10:04Z · updated 2026-10-18 10:04Z
Lane, AI role, categories and severity come from the classifier; the OWASP and ATLAS rows are derived from the categories. How these are assigned
Copy a brief
This record as a short Markdown brief, for a ticket, a chat or a coding agent.
the brief as text
# CVE-2026-67531: FrontMCP Sandbox Escape Leading to RCE https://gcdradar.vercel.app/incidents/cve-2026-67531-frontmcp-sandbox-escape-leading-to-rce · AIR-2026-1264 · closed 2026-08-06 - Lane: Patch now - Severity: 2 (Disclosed vulnerability) - Fix status: Fix status unknown - First reported: 2026-08-06 - AI role: Attack on AI - Products: FrontMCP - CVE ids: CVE-2026-67531 - CVSS: 9.3 ## Summary A sandbox escape vulnerability in FrontMCP enables scripts to leverage Proxy invariants and access the host Function constructor. This allows remote code execution in the server process via tool calls. ## What to do No action recorded; read the sources below and the vendor's advisory. ## Latest updates - 2026-08-06: CVE-2026-67531: FrontMCP is a TypeScript-first framework for the Model Context Protocol (MCP). (https://nvd.nist.gov/vuln/detail/CVE-2026-67531) ## Sources - 2026-08-06 NVD: CVE-2026-67531: FrontMCP is a TypeScript-first framework for the Model Context Protocol (MCP). https://nvd.nist.gov/vuln/detail/CVE-2026-67531 Verify against the vendor's advisory before changing production. Data CC BY-SA 4.0, https://gcdradar.vercel.app.
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AI