CVE-2026-0966
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
- Versión: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H
- Puntuación base: 8.2
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.58%
- Percentil entre todas las CVEs puntuadas: 46
- Fecha de la puntuación: 6/10/2026
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.
- Explotación
T1190Exploit Public-Facing Applicationinitial access85 % - Impacto principal
T1499.004Application or System Exploitationimpact80 %
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
- CWE-124
Referencias
- https://access.redhat.com/errata/RHSA-2026:18160
- https://access.redhat.com/errata/RHSA-2026:18683
- https://access.redhat.com/errata/RHSA-2026:7067
- https://access.redhat.com/security/cve/CVE-2026-0966
- https://bugzilla.redhat.com/show_bug.cgi?id=2433121
- https://www.libssh.org/2026/02/10/libssh-0-12-0-and-0-11-4-security-releases/
JSON original (NVD)
Mostrar
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