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CVE-2019-1836

Estado: ModificadaAlta (7.1)—

A vulnerability in the system shell for Cisco Nexus 9000 Series Fabric Switches in Application Centric Infrastructure (ACI) mode could allow an authenticated, local attacker to use symbolic links to overwrite system files. These system files may be sensitive and should not be overwritable by non-root users. The attacker would need valid device credentials. The vulnerability is due to incorrect symbolic link verification of directory paths when they are used in the system shell.

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An attacker could exploit this vulnerability by authenticating to the device and providing crafted user input to specific symbolic link CLI commands. Successful exploitation could allow the attacker to overwrite system files that should be restricted. This vulnerability has been fixed in software version 14.1(1i).

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.

Fuente: mapeo oficial MITRE CTID (CVE → ATT&CK).

🛡️ Mitigaciones ATT&CK que cubren estas técnicas

Restrict Web-Based ContentRestrict File and Directory PermissionsRemote Data StorageNetwork SegmentationMulti-factor AuthenticationLimit Access to Resource Over Network

Tecnologías afectadas (1)

Cisco — Nx-os

CWE

Referencias

JSON original (NVD)

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