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CVE-2026-4437

Estado: ModificadaAlta (7.5)—

Calling gethostbyaddr or gethostbyaddr_r with a configured nsswitch.conf that specifies the library's DNS backend in the GNU C Library version 2.34 to version 2.43 could, with a crafted response from the configured DNS server, result in a violation of the DNS specification that causes the application to treat a non-answer section of the DNS response as a valid answer.

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.

Aplicación expuesta en red (AV:N, PR:N) vulnerable a respuesta DNS malformada que causa violación de especificación (CWE-125: out-of-bounds read). La falta de validación adecuada de respuestas DNS permite DoS al consumir recursos o causar crash en aplicaciones que usan gethostbyaddr.

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

Filter Network TrafficVulnerability ScanningPrivileged Account ManagementNetwork SegmentationLimit Access to Resource Over NetworkApplication Isolation and Sandboxing

Tecnologías afectadas (1)

GNU — Glibc

CWE

Referencias

JSON original (NVD)

Mostrar
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          "userInteraction": "NONE",
          "attackComplexity": "LOW",
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