CVE-2026-20127: Cisco Catalyst SD-WAN Controller and Manager Authentication Bypass Vulnerability

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.

VendorCisco
ProductCatalyst SD-WAN Controller and Manager
Date added to KEV2026-02-25
Due date (BOD 22-01)2026-02-27
Known ransomware campaign useUnknown
CWECWE-287
Required actionPlease 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 to do

  1. Identify every instance of Cisco Catalyst SD-WAN Controller and Manager in your environment (asset inventory, EDR, vulnerability scanner).
  2. Apply CISA's 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.
  3. Federal civilian agencies must act by 2026-02-27 under BOD 22-01; other organizations can use the same date as a target.
  4. Check the vendor advisory and NVD entry linked below for affected versions, then record the fix in your change log.

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Sources

Generated from the CISA feed with AI assistance; facts are taken verbatim from the feed. Not affiliated with or endorsed by CISA. Facts come from the CISA Known Exploited Vulnerabilities catalog (public domain).