CVE-2026-11718

Katalog CVE

CVSS 9.1 · Critical EPSS 0,19%

Kerentanan Improper Authentication pada google mcp toolbox for databases. Skor CVSS 3.1 9.1 (Critical) menurut NVD.

Deskripsi (NVD)

An authentication bypass vulnerability exists in the generic opaque token validation path (validateOpaqueToken) of googleapis/mcp-toolbox. When the toolbox validates an opaque token via an OAuth 2.0 introspection endpoint (RFC 7662), it decodes the response into an introspectResp struct. However, the subsequent claim-checking logic (validateClaims) evaluates the issuer condition as if a.issuer != "" && iss != "". If the external OAuth provider's introspection response omits the optional iss (issuer) field completely, the variable iss defaults to an empty string. This causes the conditional block to evaluate to false and be skipped silently. Consequently, the application accepts tokens issued by unauthorized or unintended third-party identity providers.

Rincian

Terbit di NVD

18 Juni 2026

Terakhir diubah

17 Agustus 2026

Status NVD

Analyzed

CVSS 3.1

9.1 (Critical), sumber NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N · uraikan di kalkulator

Jenis kelemahan (CWE)

CWE-287: Improper Authentication

EPSS (30 hari)

0,19% peluang dieksploitasi; lebih tinggi dari 7,5% CVE lain

Produk dan versi terdampak

> Data dari konfigurasi CPE di NVD.

Referensi dan perbaikan

• https://github.com/googleapis/mcp-toolbox/pull/3360 patch