« Volver al listado

CVE-2026-33661

Estado: AnalizadaAlta (7.5)—

Pay is an open-source payment SDK extension package for various Chinese payment services. Prior to version 3.7.20, the `verify_wechat_sign()` function in `src/Functions.php` unconditionally skips all signature verification when the PSR-7 request reports `localhost` as the host. An attacker can exploit this by sending a crafted HTTP request to the WeChat Pay callback endpoint with a `Host: localhost` header, bypassing the RSA signature check entirely. This allows forging fake WeChat Pay payment success notifications, potentially causing applications to mark orders as paid without actual payment. Version 3.7.20 fixes the issue.

CVSS

Probabilidad de explotación (EPSS)

EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).

🎯 Técnicas ATT&CK

Cómo se explota esta vulnerabilidad y qué consigue el atacante, en el lenguaje de MITRE ATT&CK.

CVE red/AV:N sin privilegios; bypass de firma RSA enviando Host:localhost falsificado a endpoint web público. Impacto: manipulación de notificaciones de pago (T1565.002) y acceso no autorizado a funcionalidad (T1078.001).

Inferido por nuestro agente de análisis a partir de la descripción oficial, el vector CVSS y la CWE, y comprobado por un supervisor. Puede contener errores.

🛡️ Mitigaciones ATT&CK que cubren estas técnicas

Vulnerability ScanningPrivileged Account ManagementPassword PoliciesNetwork SegmentationMulti-factor AuthenticationLimit Access to Resource Over Network

Tecnologías afectadas (1)

Yansongda — PAY

CWE

Referencias

JSON original (NVD)

Mostrar
{
  "id": "CVE-2026-33661",
  "cveTags": [],
  "metrics": {
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-33661",
          "role": "CISA Coordinator",
          "options": [
            {
              "exploitation": "poc"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "version": "2.0.3",
          "timestamp": "2026-03-27T14:12:47.859453Z"
        }
      }
    ],
    "cvssMetricV31": [
      {
        "type": "Secondary",
        "source": "security-advisories@github.com",
        "cvssData": {
          "scope": "CHANGED",
          "version": "3.1",
          "baseScore": 8.6,
          "attackVector": "NETWORK",
          "baseSeverity": "HIGH",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:H/A:N",
          "integrityImpact": "HIGH",
          "userInteraction": "NONE",
          "attackComplexity": "LOW",
          "availabilityImpact": "NONE",
          "privilegesRequired": "NONE",
          "confidentialityImpact": "NONE"
        },
        "impactScore": 4,
        "exploitabilityScore": 3.9
      },
      {
        "type": "Primary",
        "source": "nvd@nist.gov",
        "cvssData": {
          "scope": "UNCHANGED",
          "version": "3.1",
          "baseScore": 7.5,
          "attackVector": "NETWORK",
          "baseSeverity": "HIGH",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N",
          "integrityImpact": "HIGH",
          "userInteraction": "NONE",
          "attackComplexity": "LOW",
          "availabilityImpact": "NONE",
          "privilegesRequired": "NONE",
          "confidentialityImpact": "NONE"
        },
        "impactScore": 3.6,
        "exploitabilityScore": 3.9
      }
    ]
  },
  "affected": [
    {
      "source": "security-advisories@github.com",
      "affectedData": [
        {
          "vendor": "yansongda",
          "product": "pay",
          "versions": [
            {
              "status": "affected",
              "version": "< 3.7.20"
            }
          ]
        }
      ]
    }
  ],
  "published": "2026-03-26T22:16:29.560",
  "references": [
    {
      "url": "https://github.com/yansongda/pay/commit/26987ebf789f1e7f0a85febb640986ab4289fd7f",
      "tags": [
        "Patch"
      ],
      "source": "security-advisories@github.com"
    },
    {
      "url": "https://github.com/yansongda/pay/releases/tag/v3.7.20",
      "tags": [
        "Release Notes"
      ],
      "source": "security-advisories@github.com"
    },
    {
      "url": "https://github.com/yansongda/pay/security/advisories/GHSA-q938-ghwv-8gvc",
      "tags": [
        "Exploit",
        "Vendor Advisory"
      ],
      "source": "security-advisories@github.com"
    },
    {
      "url": "https://github.com/yansongda/pay/security/advisories/GHSA-q938-ghwv-8gvc",
      "tags": [
        "Exploit",
        "Vendor Advisory"
      ],
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0"
    }
  ],
  "vulnStatus": "Analyzed",
  "weaknesses": [
    {
      "type": "Secondary",
      "source": "security-advisories@github.com",
      "description": [
        {
          "lang": "en",
          "value": "CWE-290"
        }
      ]
    }
  ],
  "descriptions": [
    {
      "lang": "en",
      "value": "Pay is an open-source payment SDK extension package for various Chinese payment services. Prior to version 3.7.20, the `verify_wechat_sign()` function in `src/Functions.php` unconditionally skips all signature verification when the PSR-7 request reports `localhost` as the host. An attacker can exploit this by sending a crafted HTTP request to the WeChat Pay callback endpoint with a `Host: localhost` header, bypassing the RSA signature check entirely. This allows forging fake WeChat Pay payment success notifications, potentially causing applications to mark orders as paid without actual payment. Version 3.7.20 fixes the issue."
    },
    {
      "lang": "es",
      "value": "Pay es un paquete de extensión de SDK de pago de código abierto para varios servicios de pago chinos. Antes de la versión 3.7.20, la función `verify_wechat_sign()` en `src/Functions.php` omite incondicionalmente toda la verificación de firma cuando la solicitud PSR-7 informa localhost como el host. Un atacante puede explotar esto enviando una solicitud HTTP manipulada al endpoint de callback de WeChat Pay con un encabezado Host: localhost, eludiendo por completo la verificación de firma RSA. Esto permite falsificar notificaciones de éxito de pago falsas de WeChat Pay, lo que podría hacer que las aplicaciones marquen los pedidos como pagados sin un pago real. La versión 3.7.20 corrige el problema."
    }
  ],
  "lastModified": "2026-06-17T10:37:52.897",
  "configurations": [
    {
      "nodes": [
        {
          "negate": false,
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:a:yansongda:pay:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "EB442148-12BE-4EE8-A5C6-99501BC4C1B2",
              "versionEndExcluding": "3.7.20"
            }
          ],
          "operator": "OR"
        }
      ]
    }
  ],
  "sourceIdentifier": "security-advisories@github.com"
}