CVE-2026-20127

10.0 CRITICAL 88% exploit odds Drop everything exploited in the wild Fix listed Auth & access Network gear

What it is

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. 

At a glance

Exploitability: Can be exploited over the network without logging in. High risk of data exposure, data tampering, service disruption.
In the wild: CISA lists this as exploited in real attacks. Treat as urgent.
Fix: A patch, advisory or fixed version is referenced. Upgrade or apply it.

Timeline

2025-10-08 11:59 UTC ReservedThe CVE id was reserved by its CNA
2026-02-25 Exploited in the wildAdded to CISA's Known Exploited Vulnerabilities list
2026-02-25 17:25 UTC PublishedDisclosed publicly on CVE.org and NVD
2026-02-27 Remediation deadlineCISA's due date for federal agencies to fix it
2026-06-17 15:06 UTC Last updatedMost recent change to the record