CVE-2026-20127: Cisco Catalyst SD-WAN Controller Authentication Bypass Vulnerability
On February 25, 2026, Cisco released fixes for a maximum severity authentication bypass vulnerability in Cisco Catalyst SD-WAN Controller (formerly vSmart) and Cisco Catalyst SD-WAN Manager (formerly vManage), tracked as CVE-2026-20127. The flaw arises from a broken peering authentication mechanism in the control-plane authentication workflow. This vulnerability potentially allows a remote, unauthenticated threat actor to bypass authentication and obtain administrative privileges on an affected system.