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CVE-2026-59851

Estado: ModificadaAlta (8.8)—

A flaw was found in libssh. On servers with GSSAPIKeyExchange enabled, the gssapi-keyex path does not verify whether the authenticated Kerberos principal is authorized for the requested local user, allowing authenticated clients to log in as arbitrary users.

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.

Acceso remoto autenticado (AV:N PR:L) sin validación de autorización en Kerberos permite suplantar usuarios locales arbitrarios; impacto: acceso con identidad falsificada y potencial creación de cuentas administrativas.

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

Privileged Account ManagementMulti-factor AuthenticationDisable or Remove Feature or ProgramVulnerability ScanningThreat Intelligence ProgramPassword Policies

Tecnologías afectadas (3)

Libssh — LibsshRedhat — Enterprise LinuxRedhat — Hardened Images

CWE

Referencias

JSON original (NVD)

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