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CVE-2026-0966

Estado: ModificadaAlta (8.2)—

A flaw was found in libssh. The API function `ssh_get_hexa()` is vulnerable to a denial of service when processing zero-length input. This can be exploited remotely by an attacker during GSSAPI (Generic Security Service Application Program Interface) authentication if the server's logging verbosity is set to `SSH_LOG_PACKET (3)` or higher. Successful exploitation could lead to a self-Denial of Service of the per-connection daemon process.

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 en libssh sin autenticación previa (AV:N, PR:N, UI:N) explotable en GSSAPI. CWE-124 (buffer underread) causa DoS del proceso daemon (A:H). T1499.004 (application exhaustion).

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

Tecnologías afectadas (4)

CWE

Referencias

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      "value": "A flaw was found in libssh. The API function `ssh_get_hexa()` is vulnerable to a denial of service when processing zero-length input. This can be exploited remotely by an attacker during GSSAPI (Generic Security Service Application Program Interface) authentication if the server's logging verbosity is set to `SSH_LOG_PACKET (3)` or higher. Successful exploitation could lead to a self-Denial of Service of the per-connection daemon process."
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      "value": "La función API 'ssh_get_hexa()' es vulnerable cuando se proporciona una entrada de longitud 0 a esta función. Esta función se utiliza internamente en 'ssh_get_fingerprint_hash()' y 'ssh_print_hexa()' (obsoleta), la cual es vulnerable a la misma entrada (la longitud es proporcionada por la aplicación que realiza la llamada).\n\nLa función también se utiliza internamente en el código gssapi para registrar los OID recibidos por el servidor durante la autenticación GSSAPI. Esto podría activarse de forma remota cuando el servidor permite la autenticación GSSAPI y la verbosidad del registro se establece al menos en SSH_LOG_PACKET (3). Esto podría causar un auto-DoS del proceso demonio por conexión."
    }
  ],
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