CVE-2026-77321 (GCVE-0-2026-77321)

Vulnerability from cvelistv5 – Published: 2026-09-24 18:04 – Updated: 2026-09-24 18:04
VLAI
Title
TREK MCP trip summary bypasses delegated OAuth read scopes
Summary
TREK is a collaborative travel planner. Prior to 3.3.0, the get_trip_summary tool in server/src/mcp/tools/trips.ts is registered for scoped OAuth MCP tokens without requiring trips:read and returns core trip summary data regardless of the delegated scopes. A token granted only an unrelated capability, such as weather:read, can receive trip metadata, member email addresses from server/src/services/tripService.ts, itinerary days, and accommodations for every trip accessible to the token's user. Cross-user trip authorization remains enforced, but the missing scope check defeats the consented least-privilege boundary and exposes trip content and third-party contact information to an MCP client that was not authorized to read it. This issue is fixed in version 3.3.0.
Severity
4.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
CWE
  • CWE-200 - Exposure of Sensitive Information to an Unauthorized Actor
  • CWE-284 - Improper Access Control
  • CWE-862 - Missing Authorization
Assigner
References
Impacted products
Vendor Product Version CPE status
mauriceboe TREK Affected: < 3.3.0
guessed Create a notification for this product.
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          "value": "TREK is a collaborative travel planner. Prior to 3.3.0, the get_trip_summary tool in server/src/mcp/tools/trips.ts is registered for scoped OAuth MCP tokens without requiring trips:read and returns core trip summary data regardless of the delegated scopes. A token granted only an unrelated capability, such as weather:read, can receive trip metadata, member email addresses from server/src/services/tripService.ts, itinerary days, and accommodations for every trip accessible to the token\u0027s user. Cross-user trip authorization remains enforced, but the missing scope check defeats the consented least-privilege boundary and exposes trip content and third-party contact information to an MCP client that was not authorized to read it. This issue is fixed in version 3.3.0."
        }
      ],
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              "description": "CWE-862: Missing Authorization",
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              "type": "CWE"
            }
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        "dateUpdated": "2026-09-24T18:04:05.947Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
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          "name": "https://github.com/liketrek/TREK/security/advisories/GHSA-qvw8-w937-vcmq",
          "tags": [
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          "url": "https://github.com/liketrek/TREK/security/advisories/GHSA-qvw8-w937-vcmq"
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        {
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          "tags": [
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          "url": "https://github.com/liketrek/TREK/pull/1520"
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      ],
      "source": {
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        "discovery": "UNKNOWN"
      },
      "title": "TREK MCP trip summary bypasses delegated OAuth read scopes"
    }
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  "cveMetadata": {
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    "cveId": "CVE-2026-77321",
    "datePublished": "2026-09-24T18:04:05.947Z",
    "dateReserved": "2026-08-20T19:24:11.617Z",
    "dateUpdated": "2026-09-24T18:04:05.947Z",
    "state": "PUBLISHED"
  },
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  "dataVersion": "5.2",
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    "nvd": {
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          }
        ],
        "id": "CVE-2026-77321",
        "lastModified": "2026-09-25T13:17:26.220",
        "metrics": {
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}



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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

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Nomenclature

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