Vulnerability identifier: #VU25670

Vulnerability risk: Low

CVSSv3.1: 4.1 [CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N/E:U/RL:O/RC:C]

CVE-ID: CVE-2020-3174

CWE-ID: CWE-345

Exploitation vector: Local 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 a device to learn invalid Address Resolution Protocol (ARP) entries.

The vulnerability exists due to improper validation of a received gratuitous ARP (GARP) request in the anycast gateway feature. A remote attacker on the local network can send a malicious GARP packet to cause the ARP table on the device to become corrupted and populate the ARP table with incorrect entries, which could lead to traffic disruptions.

This vulnerability affects the following products if they are running a vulnerable release of Cisco NX-OS Software and had the anycast gateway feature enabled:

• Nexus 3000 Series Switches
• Nexus 7000 Series Switches
• Nexus 9000 Series Switches in standalone NX-OS mode

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Cisco NX-OS: 8.1.1 - 9.3.1

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External links
http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20200226-nxos-arp

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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 local network (LAN).

Is there known malware, which exploits this vulnerability?

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