CVE-2026-26158
A flaw was found in BusyBox. This vulnerability allows an attacker to modify files outside of the intended extraction directory by crafting a malicious tar archive containing unvalidated hardlink or symlink entries. If the tar archive is extracted with elevated privileges, this flaw can lead to privilege escalation, enabling an attacker to gain unauthorized access to critical system files.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H
- Puntuación base: 7
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.18%
- Percentil entre todas las CVEs puntuadas: 6
- 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.
- Explotación
T1203Exploitation for Client Executionexecution85 % - Impacto principal
T1068Exploitation for Privilege Escalationprivilege escalation90 % - Impacto secundario
T1565.001Stored Data Manipulationimpact80 %
Requiere interacción del usuario (UI:R) para extraer archivo tar malicioso; escalada de privilegios si se ejecuta con permisos elevados. Modificación de archivos fuera del directorio previsto mediante enlaces simbólicos no validados.
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
Tecnologías afectadas (1)
⚠ Inferidas por IA a partir de la descripción — NVD aún no ha analizado esta CVE; no son CPE verificados.
CWE
- CWE-73
- CWE-73
Referencias
- https://access.redhat.com/errata/RHSA-2026:13831
- https://access.redhat.com/security/cve/CVE-2026-26158
- https://bugzilla.redhat.com/show_bug.cgi?id=2439040
- https://git.busybox.net/busybox/commit/archival?id=3fb6b31c716669e12f75a2accd31bb7685b1a1cb
- https://access.redhat.com/errata/RHSA-2026:13831
- https://access.redhat.com/security/cve/CVE-2026-26158
- https://bugzilla.redhat.com/show_bug.cgi?id=2439040
- https://cert-portal.siemens.com/productcert/html/ssa-253495.html
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-26158.json
JSON original (NVD)
Mostrar
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