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CVE-2026-55999

Estado: AnalizadaAlta (7.8)—

Local attackers with a X connection able to provide PCX fonts to the X server xorg-server before 21.2.24 and xwayland before 24.1.13 could cause a heap buffer overflow via SetFont due to missing glyph boundary checks.

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.

AV:L sin UI:R indica escalada local sin interacción (T1068). El overflow de heap permite ejecución de código (T1059) y posible DoS (T1499.004) en servidor X.

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

Execution PreventionThreat Intelligence ProgramRestrict Web-Based ContentPrivileged Account ManagementLimit Software InstallationFilter Network Traffic

Tecnologías afectadas (2)

X.org — X ServerX.org — Xwayland

CWE

Referencias

JSON original (NVD)

Mostrar
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