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CVE-2019-1836

Status: ModifiedHigh (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

Exploitation probability (EPSS)

EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).

🎯 ATT&CK techniques

How this vulnerability is exploited and what the attacker gains, in MITRE ATT&CK terms.

Source: official MITRE CTID mapping (CVE → ATT&CK).

🛡️ ATT&CK mitigations that cover these techniques

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

Affected technologies (1)

Cisco — Nx-os

CWEs

References

Raw JSON (NVD)

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