{
  "entry": {
    "kind": "vuln",
    "slug": "cve-2026-40576",
    "name": "CVE-2026-40576",
    "vendor": "excel-mcp-server",
    "description": "A path traversal flaw in excel-mcp-server let unauthenticated attackers read, write and overwrite arbitrary files. Its get_excel_path() passed absolute paths through without validation and failed to resolve ../ traversal sequences, and because the server binds to all network interfaces with no authentication by default, remote exploitation was straightforward. This is the recurring shape of MCP server risk: the code flaw is ordinary, but the default deployment posture turns it into remote file write.",
    "website": "https://www.sentinelone.com/vulnerability-database/cve-2026-40576/",
    "repository": null,
    "documentationUrl": null,
    "license": null,
    "version": null,
    "trustLevel": "advisory",
    "capabilities": [],
    "packaging": null,
    "configFiles": null,
    "category": "mcp-server",
    "updatedAt": "2026-04-23",
    "risk": {
      "score": 94,
      "band": "critical",
      "signals": [],
      "dangerousCombos": []
    },
    "dangerousCombos": [],
    "vuln": {
      "id": "CVE-2026-40576",
      "aliases": [
        "ti-060"
      ],
      "title": "CVE-2026-40576: excel-mcp-server Path Traversal Allows Unauthenticated File Read and Overwrite (CVSS 9.4)",
      "summary": "A path traversal flaw in excel-mcp-server let unauthenticated attackers read, write and overwrite arbitrary files. Its get_excel_path() passed absolute paths through without validation and failed to resolve ../ traversal sequences, and because the server binds to all network interfaces with no authentication by default, remote exploitation was straightforward. This is the recurring shape of MCP server risk: the code flaw is ordinary, but the default deployment posture turns it into remote file write.",
      "severity": "critical",
      "cvss": {
        "score": 9.4,
        "vector": null,
        "version": null
      },
      "cwe": [],
      "attackType": [
        "Path traversal"
      ],
      "componentType": "mcp-server",
      "component": {
        "name": "excel-mcp-server",
        "vendor": null,
        "package": null,
        "ecosystem": null,
        "catalogSlug": null
      },
      "affected": [
        {
          "range": "excel-mcp-server <= 0.1.7 (fixed in 0.1.8)",
          "fixed": "0.1.8"
        }
      ],
      "exploited": false,
      "exploitPublic": false,
      "publishedAt": "2026-04-23",
      "modifiedAt": "2026-04-23",
      "lastVerified": "2026-11-01",
      "references": [
        {
          "type": "article",
          "url": "https://www.sentinelone.com/vulnerability-database/cve-2026-40576/"
        },
        {
          "type": "cve",
          "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-40576"
        }
      ],
      "mitigation": "Upgrade excel-mcp-server to 0.1.8+. Bind MCP servers to 127.0.0.1 rather than 0.0.0.0, put authentication in front of any MCP server reachable off-host, and run file-handling MCP servers against a scoped or read-only filesystem.",
      "detectedByAnomity": true
    }
  }
}