CVE-2026-12244

Estado: AnalizadaAlta (8.7)—

If NSD is configured as secondary for a zone, the primary of that zone can crash NSD with an AXFR containing a DNS message with a special crafted SVCB RR with an rdata size of 65512, that let's an (uint16_t) variable that is used to allocate space needed for the RR wrap (because total size > 65535), causing a heap overflow. The attacker can perform a controlled (RCE class) head write of up to 65509 bytes

CVSS

Versión: 4.0
Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Puntuación base: 8.7

Probabilidad de explotación (EPSS)

Probabilidad de explotación en los próximos 30 días: 0.49%
Percentil entre todas las CVEs puntuadas: 40
Fecha de la puntuación: 5/10/2026

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.

ExplotaciónT1210 Exploitation of Remote Serviceslateral movement92 %
Impacto principalT1059 Command and Scripting Interpreterexecution85 %
Impacto secundarioT1068 Exploitation for Privilege Escalationprivilege escalation78 %

AV:N/PR:L requiere privilegios en red adyacente (servidor primario autorizado). Heap overflow en AXFR permite RCE controlado (65509 bytes); impacto: ejecución código y potencial escalada administrativa del demonio NSD.

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

Threat Intelligence Program Privileged Account Management Execution Prevention Disable or Remove Feature or Program Application Isolation and Sandboxing Exploit Protection

Tecnologías afectadas (1)

Nlnetlabs — NSD

CWE

CWE-122, CWE-190

Referencias

https://www.nlnetlabs.nl/downloads/nsd/CVE-2026-12244.txt

JSON original (NVD)

Mostrar

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