No. CVE-2026-20127
A Cisco Catalyst SD-WAN Controller and Manager bug is being used in attacks
Yes. Attackers are using this right now.
What to do
Apply the vendor's update. If there is none, stop using it or cut it off from the internet.
- Confirmed in attacks
- Feb 25, 2026
- Product
- Cisco Catalyst SD-WAN Controller and Manager
- Attack likelihood, next 30 days
- 89%
Attack likelihood is EPSS, a daily estimate from FIRST.org of how likely this bug is to be used in attacks in the next 30 days.
The official description
Cisco Catalyst SD-WAN Controller, formerly SD-WAN vSmart, and Cisco Catalyst SD-WAN Manager, formerly SD-WAN vManage, contain an authentication bypass vulnerability 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.
For your tech helper
A read-only checklist for whoever helps you with your computer, or an AI assistant. Paste it into Claude, ChatGPT or a coding agent; it only looks and changes nothing.
Read-only check, change nothing, send nothing anywhere.
Is Cisco Catalyst SD-WAN Controller and Manager (CVE-2026-20127) installed or running on this machine or in this project?
1. Find every copy and its version (apps, packages, containers, lockfiles).
2. Compare each version against the vendor's fixed version for CVE-2026-20127. Quote the vendor page you used.
3. Report a table: where, version, fixed version, status (exposed / fixed / not installed / unsure).
4. List the exact update steps, but do not run them.