Vulnerability identifier: #VU20489

Vulnerability risk: High

CVSSv3.1: 7.5 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2019-1964

CWE-ID: CWE-20

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Cisco NX-OS
Operating systems & Components / Operating system

Vendor: Cisco Systems, Inc

Description

The vulnerability allows a remote attacker to cause an unexpected restart of the netstack process on an affected device.

The vulnerability exists due to improper validation of IPv6 traffic sent through an affected device. A remote attacker can send a malformed IPv6 packet through an affected device, cause a denial of service (DoS) condition while the netstack process restarts. A sustained attack could lead to a reboot of the device.

This vulnerability affects the following products that are running a Cisco NX-OS Software:

• Nexus 7000 Series Switches
• Nexus 7700 Series Switches

Mitigation
Install update from vendor's website.

Vulnerable software versions

Cisco NX-OS: 8.1 - 8.3

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External links
http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190828-nxos-ipv6-dos

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.