CVE-2026-45186

Estado: ModificadaAlta (7.5)—
In libexpat before 2.8.1, the computational complexity of attribute name collision checks allows a denial of service via moderately sized crafted XML input.
CVSS

Versión: 3.1
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Puntuación base: 7.5
Probabilidad de explotación (EPSS)

Probabilidad de explotación en los próximos 30 días: 0.48%
Percentil entre todas las CVEs puntuadas: 39
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.
ExplotaciónT1190 Exploit Public-Facing Applicationinitial access85 %
Impacto principalT1499.004 Application or System Exploitationimpact90 %
Aplicación expuesta (libexpat en parseo XML remoto) explotable sin autenticación ni interacción; vector CVSS AV:N/PR:N/UI:N confirma T1190. La complejidad computacional de validación causa DoS (A:H en CVSS), clasificado como T1499.004 (consumo de recursos de aplicación).
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 Traffic Vulnerability Scanning Privileged Account Management Network Segmentation Limit Access to Resource Over Network Application Isolation and Sandboxing
Tecnologías afectadas (1)

Libexpat Project — Libexpat
CWE

CWE-407
CWE-407
Referencias

JSON original (NVD)

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