CVE-2020-3170: Cisco NX-OS

Medium severity, CVSS 5.3. EPSS: 1.7% chance of exploitation in the next 30 days.

A vulnerability in the NX-API feature of Cisco NX-OS Software could allow an unauthenticated, remote attacker to cause an NX-API system process to unexpectedly restart. The vulnerability is due to incorrect validation of the HTTP header of a request that is sent to the NX-API. An attacker could exploit this vulnerability by sending a crafted HTTP request to the NX-API on an affected device. A successful exploit could allow the attacker to cause a denial of service (DoS) condition in the NX-API service; however, the Cisco NX-OS device itself would still be available and passing network traffic. Note: The NX-API feature is disabled by default.

Affected products

• Cisco NX-OS: before 8.4\(1\) (fixed in 8.4\(1\)); before 8.2\(5\) (fixed in 8.2\(5\))

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