Cisco Nexus 1000V Switch for VMware vSphere Secure Login Enhancements Denial of Service Vulnerability

published 2020-02-26 6y ago modified 2026-06-17 4mo ago also EUVD-2020-24439

cvss: 7.5; version 3.0, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 1.6%; EPSS 1.6% chance of exploitation in 30 days, percentile 75%
public exploits: 0; none known

A vulnerability in the Secure Login Enhancements capability of Cisco Nexus 1000V Switch for VMware vSphere could allow an unauthenticated, remote attacker to cause an affected Nexus 1000V Virtual Supervisor Module (VSM) to become inaccessible to users through the CLI. The vulnerability is due to improper resource allocation during failed CLI login attempts when login parameters that are part of the Secure Login Enhancements capability are configured on an affected device. An attacker could exploit this vulnerability by performing a high amount of login attempts against the affected device. A successful exploit could cause the affected device to become inaccessible to other users, resulting in a denial of service (DoS) condition requiring a manual power cycle of the VSM to recover.

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CISA SSVC

Exploitation: none
Automatable: yes
Technical impact: partial
Assessed: last yr. (2024-11-15)

Exploit prediction

1.60% chance of exploitation in the next 30 days, higher than 75% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by	version	score	vector
CNA	3.0	7.5	CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
NVD	3.1	7.5	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
NVD	2.0	7.1	AV:N/AC:M/Au:N/C:N/I:N/A:C

Affected products

Cisco Cisco NX-OS Software

Classification

Weakness

CWE-399 Resource Management Errors
CWE-400 Uncontrolled Resource Consumption

References

tools.cisco.com /security/center/content/CiscoSecurityAdvisory/cisco-sa-20200226-nexus-1000v-dos
vendor-advisory

Sources

CVE List CVE-2020-3168
NVD CVE-2020-3168

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