CVE-2020-3174: Cisco NX-OS

Medium severity, CVSS 4.7. EPSS: 0.3% chance of exploitation in the next 30 days.

A vulnerability in the anycast gateway feature of Cisco NX-OS Software could allow an unauthenticated, adjacent attacker to cause a device to learn invalid Address Resolution Protocol (ARP) entries. The ARP entries are for nonlocal IP addresses for the subnet. The vulnerability is due to improper validation of a received gratuitous ARP (GARP) request. An attacker could exploit this vulnerability by sending a malicious GARP packet on the local subnet to cause the ARP table on the device to become corrupted. A successful exploit could allow the attacker to populate the ARP table with incorrect entries, which could lead to traffic disruptions.

Affected products

• Cisco NX-OS: version 8.1(1) only; version 8.4(1) only; version 9.3(1) only

Published 2020-02-26. Last modified 2026-06-17.