Actively exploited in the wild
Cisco Catalyst SD-WAN Controller and Manager Authentication Bypass Vulnerability
Cisco — Catalyst SD-WAN Controller and Manager · Listed in the CISA KEV since 2026-02-25. This indicates confirmed attacks in production environments.
Required action: Please adhere to CISA’s guidelines to assess exposure and mitigate risks associated with Cisco SD-WAN devices as outlines in CISA’s Emergency Directive 26-03 (URL listed below in Notes) and CISA’s “Hunt & Hardening Guidance for Cisco SD-WAN Devices (URL listed below in Notes). Adhere to the applicable BOD 22-01 guidance for cloud services or discontinue use of the product if mitigations are not available.
CVE-2026-20127
CriticalCVSS 10.0KEVExploitation Probability (EPSS)
Very high risk99th percentile — higher than 99% of all known CVEs
Summary
A vulnerability in the peering authentication mechanism in Cisco Catalyst SD-WAN Controller, Manager, and Validator allows an unauthenticated remote attacker to bypass the login process and gain administrative privileges on an affected system.
Risk Assessment
An attacker could exploit this vulnerability to manipulate the SD-WAN network configuration, potentially leading to serious security breaches within the organization.
Recommendation
It is recommended to update the software to the latest version to patch this vulnerability and to monitor systems for unauthorized access attempts.
Original NVD description (English source)
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.