CVE-2019-1964
highpriority · track · 31EPSS 0.020 · 80 %ileEURUUSEPSS · scored 2026-10-27
A vulnerability in the IPv6 traffic processing of Cisco NX-OS Software could allow an unauthenticated, remote attacker to cause an unexpected restart of the netstack process on an affected device. The vulnerability is due to improper validation of IPv6 traffic sent through an affected device. An attacker could exploit this vulnerability by sending a malformed IPv6 packet through an affected device. A successful exploit could allow the attacker to cause a denial of service (DoS) condition while the netstack process restarts. A sustained attack could lead to a reboot of the device.
remediations
Vendor fix, mitigation, or workaround guidance, as published by each source.
A vendor fix is available.
- FixedCisco NX-OS Software 8.1(1) when installed on Cisco Nexus 7000 Series Switchescisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - FixedCisco NX-OS Software 8.1(2) when installed on Cisco Nexus 7000 Series Switchescisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - FixedCisco NX-OS Software 8.1(2a) when installed on Cisco Nexus 7000 Series Switchescisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - FixedCisco NX-OS Software 8.2(1) when installed on Cisco Nexus 7000 Series Switchescisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - FixedCisco NX-OS Software 8.2(2) when installed on Cisco Nexus 7000 Series Switchescisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - FixedCisco NX-OS Software 8.3(1) when installed on Cisco Nexus 7000 Series Switchescisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - FixedCisco NX-OS Software 8.3(2) when installed on Cisco Nexus 7000 Series Switchescisco_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 · 6.9–8.6
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (12)
Products and version ranges known to be affected.
advisories (1)
Vendor and ecosystem advisories describing this.
- cisco-sa-20190828-nxos-ipv6-dosCisco NX-OS Software IPv6 Denial of Service Vulnerability2019-08-28csaf · cisco_csafUS
A vulnerability in the IPv6 traffic processing of Cisco NX-OS Software could allow an unauthenticated, remote attacker to cause an unexpected restart of the netstack process on an affected device. The vulnerability is due to improper validation of IPv6 traffic sent through an affected device. An attacker could exploit this vulnerability by sending a malformed IPv6 packet through an affected device. A successful exploit could allow the attacker to cause a denial of service (DoS) condition while the netstack process restarts. A sustained attack could lead to a reboot of the device. Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability. This advisory is available at the following link: https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190828-nxos-ipv6-dos ["https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190828-nxos-ipv6-dos"] This advisory is part of the August 2019 Cisco FXOS and NX-OS Software Security Advisory Bundled Publication, which includes five Cisco Security Advisories that describe five vulnerabilities. For a complete list of the advisories and links to them, see Cisco Event Response: August 2019 Cisco FXOS and NX-OS Software Security Advisory Bundled Publication ["https://sec.cloudapps.cisco.com/security/center/viewErp.x?alertId=ERP-72243"].
also known as (4)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (13)
External citations — patches, advisories, analysis.
- https://nvd.nist.gov/vuln/detail/CVE-2019-1964cnnvd
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190828-fxnxos-snmp-doscnnvd
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190828-nxos-api-doscnnvd
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190828-nxos-fsip-doscnnvd
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190828-nxos-ipv6-doscnnvd
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190828-nxos-memleak-doscnnvd
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190828-nxos-ntp-doscnnvd
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190828-nxos-snmp-bypasscnnvd
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