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CVE-2026-58083

Estado: AnalizadaAlta (8.4)—

While the kernel was copying knotes during fork, a knote with a timer-based filter could fire and be enqueued on the kqueue's active list before the copy was complete. The copy routine did not account for this and could enqueue the new knote a second time, corrupting the active list. In addition, the copy routine did not hold the appropriate locks while reading knote state, allowing further races.

An unprivileged local user can trigger a use-after-free in the kernel, potentially leading to privilege escalation.

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.

CVE-2026-58083 es una vulnerabilidad local (AV:L, PR:N) sin interacción del usuario (UI:N) que permite a un atacante sin privilegios ejecutar código en kernel mediante use-after-free (CWE-416) durante fork de knotes. Afecta a FreeBSD kernel, permitiendo escalada de privilegios.

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 InstallationBehavior Prevention on Endpoint

Tecnologías afectadas (1)

Freebsd — Freebsd

CWE

Referencias

JSON original (NVD)

Mostrar
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      "tags": [
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  "lastModified": "2026-08-31T19:02:30.440",
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