Exploited vulnerability · CISA KEV

Is CVE-2026-20127 exploited? Yes: in CISA KEV since 25 Feb 2026

Gociux · Cisco Catalyst SD-WAN Controller and Manager · data: CISA KEV, CVE record, FIRST EPSS

Yes. CVE-2026-20127, Cisco Catalyst SD-WAN Controller and Manager Authentication Bypass Vulnerability, is being exploited in the wild. CISA added it to its Known Exploited Vulnerabilities catalog on 25 Feb 2026, the day it was published. It affects Cisco Catalyst SD-WAN Controller and Manager. If you run it, CISA's required action is: 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.

What it is

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.

What to do

1. Check whether you run it. Look for Catalyst SD-WAN Controller and Manager in your asset inventory, including appliances and cloud images. Stack check lists every exploited Cisco CVE at once.
2. Apply the fix. 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.
3. If you can't patch today, take the affected service off the internet or restrict who can reach it, and check its logs for signs of compromise since 25 Feb 2026.
4. Get told next time. Email alerts when CISA adds a CVE for Cisco.

References

• www.cisa.gov/news-events/directives/supplemental-direction-ed-26-03-hunt
• sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-sdwa
• nvd.nist.gov/vuln/detail/CVE-2026-20127

Sources: CISA KEV (exploitation, ransomware use, required action, due date), the CVE record (publication date, CVSS, CNA), NVD and FIRST EPSS (live score). More: all KEV additions in February 2026 · Cisco scorecard · act-now radar.