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CVE-2026-73314

Estado: AnalizadaAlta (8.7)—

XenForo before 2.3.13 contains a signature verification logic error in the PayPal REST webhook handler that allows unauthenticated attackers to bypass payment signature validation by submitting a webhook request with an unsupported auth_algo header value. When the algorithm cannot be mapped to a supported hash function, the verification function incorrectly returns true instead of failing, causing the caller to treat the fabricated request as verified and process the payment event without a valid PayPal signature.

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.

Vulnerabilidad remota sin autenticación (AV:N/PR:N/UI:N) en lógica de verificación de webhooks PayPal que permite falsificar eventos de pago e inyectar datos fraudulentos (VI:H) en la plataforma de comercio electrónico.

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

Network SegmentationVulnerability ScanningRestrict File and Directory PermissionsPrivileged Account ManagementPassword PoliciesMulti-factor Authentication

Tecnologías afectadas (1)

Xenforo — Xenforo

CWE

Referencias

JSON original (NVD)

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