CVE-2026-20127

Cisco Catalyst SD-WAN Controller Authentication Bypass Vulnerability

Severity
Critical 10
CVSS 3.1
Exploited
Yes — in CISA KEV
Added Feb 25, 2026
EPSS
0.882
99.8th percentile
Discovered by
Vendor
Published by the vendor
Published
Feb 25, 2026
Assigned by cisco

Description

A vulnerability in the peering authentication in Cisco Catalyst SD-WAN Controller, formerly SD-WAN vSmart, Cisco Catalyst SD-WAN Manager, formerly SD-WAN vManage, and Cisco Catalyst SD-WAN Validator, formerly SD-WAN vBond, could allow an unauthenticated, remote attacker to bypass authentication and obtain administrative privileges on an affected system. This vulnerability exists because the peering authentication mechanism in an affected system is not working properly. An attacker could exploit this vulnerability by sending crafted requests to an affected system. A successful exploit could allow the attacker to log in to an affected Cisco Catalyst SD-WAN Controller as an internal, high-privileged, non-root user account. Using this account, the attacker could access NETCONF, which would then allow the attacker to manipulate network configuration for the SD-WAN fabric. 

Weakness: CWE-287

Affected products

Vendor Product Category Matched by
Cisco Cisco Catalyst SD-WAN Manager Network & Security Management cna-assigner
Vendor-reported affected versions (1)
  • Cisco · Cisco Catalyst SD-WAN Manager