CVE-2020-3168
highpriority · track · 31EPSS 0.016 · 76 %ileEURUUSEPSS · scored 2026-10-27
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.
remediations
Vendor fix, mitigation, or workaround guidance, as published by each source.
A vendor fix is available.
- FixedCisco NX-OS Softwarecisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 6.9–7.5
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (4)
Products and version ranges known to be affected.
advisories (1)
Vendor and ecosystem advisories describing this.
- cisco-sa-20200226-nexus-1000v-dosCisco Nexus 1000V Switch for VMware vSphere Secure Login Enhancements Denial of Service Vulnerability2020-02-26csaf · cisco_csafUS
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. Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability. This advisory is part of the February 2020 Cisco FXOS and NX-OS Software Security Advisory Bundled Publication, which includes six Cisco Security Advisories that describe six vulnerabilities. For a complete list of the advisories and links to them, see Cisco Event Response: February 2020 Cisco FXOS and NX-OS Software Security Advisory Bundled Publication ["https://sec.cloudapps.cisco.com/security/center/viewErp.x?alertId=ERP-73749"].
also known as (4)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (7)
External citations — patches, advisories, analysis.
- http://www.nsfocus.net/vulndb/46036cnnvd
- https://nvd.nist.gov/vuln/detail/CVE-2020-3168cnnvd
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20200226-nexus-1000v-doscnnvd
- https://vigilance.fr/vulnerability/Cisco-Nexus-1000V-Switch-for-VMware-vSphere-denial-of-service-via-VSM-Secure-Login-Enhancements-31685cnnvd
- https://www.auscert.org.au/bulletins/ESB-2020.0710/cnnvd
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20200226-nexus-1000v-dosenisa_euvd
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20200226-nexus-1000v-dosVendor Advisorynvd
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