CVE-2021-34726: Cisco SD-WAN

Medium severity, CVSS 6.7. EPSS: 0.4% chance of exploitation in the next 30 days.

A vulnerability in the CLI of Cisco SD-WAN Software could allow an authenticated, local attacker to inject arbitrary commands to be executed with root-level privileges on the underlying operating system of an affected device. This vulnerability is due to insufficient input validation on certain CLI commands. An attacker could exploit this vulnerability by authenticating to an affected device and submitting crafted input to the CLI. The attacker must be authenticated as an administrative user to execute the affected commands. A successful exploit could allow the attacker to execute commands with root-level privileges.

Affected products

• Cisco SD-WAN: before 18.4.6 (fixed in 18.4.6); from 19.2.0, before 19.2.3 (fixed in 19.2.3); from 20.1, before 20.1.2 (fixed in 20.1.2); from 20.3, before 20.3.1 (fixed in 20.3.1); from 20.4, before 20.4.1 (fixed in 20.4.1); from 20.5, before 20.5.1 (fixed in 20.5.1)

Published 2021-09-23. Last modified 2026-06-17.