CVE-2026-20129: Cisco Catalyst SD-WAN Manager

Critical severity, CVSS 9.8. EPSS: 0.7% chance of exploitation in the next 30 days.

A vulnerability in the API user authentication of Cisco Catalyst SD-WAN Manager could allow an unauthenticated, remote attacker to gain access to an affected system as a user who has the netadmin role. The vulnerability is due to improper authentication for requests that are sent to the API. An attacker could exploit this vulnerability by sending a crafted request to the API of an affected system. A successful exploit could allow the attacker to execute commands with the privileges of the netadmin role. Note: Cisco Catalyst SD-WAN Manager releases 20.18 and later are not affected by this vulnerability. 

Affected products

• Cisco Catalyst SD-WAN Manager: before 20.9.8.2 (fixed in 20.9.8.2); from 20.11, before 20.12.5.3 (fixed in 20.12.5.3); from 20.13, before 20.15.4.2 (fixed in 20.15.4.2); from 20.16, before 20.18 (fixed in 20.18); version 20.12.6 only

Published 2026-02-25. Last modified 2026-06-17.