CVE-2026-20127
Cisco Catalyst SD-WAN Controller and Manager Authentication Bypass Vulnerability
This vulnerability is in the CISA Known Exploited Vulnerabilities catalog: attackers are using it. If you run Catalyst SD-WAN Controller and Manager, fix it now.
CISA 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.
US federal civilian agencies must remediate by Feb 27, 2026.
Patch status
No official fix confirmed yet
Until a fix ships, follow the vendor's mitigations and CISA's required action, limit exposure of affected systems, and watch this record for a patch.
Description
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.
Source: NIST National Vulnerability Database. Official vulnerability data, reproduced as published.
Affected products
| Product | Vendor | Affected versions | Fixed in | Source |
|---|---|---|---|---|
| Catalyst SD-WAN Controller and Manager | Cisco | — | — | KEV |
| Catalyst SD-WAN Manager | Cisco | < 20.9.8.2; >= 20.11, < 20.12.5.3; >= 20.13, < 20.15.4.2; >= 20.16, < 20.18.2.1; 20.12.6 | 20.9.8.2; 20.12.5.3; 20.15.4.2; 20.18.2.1 | NVD |
Sources: KEV = CISA Known Exploited Vulnerabilities catalog; NVD = NIST National Vulnerability Database.
Intelligence timeline
Developments from the last 30 days, newest first.
No developments recorded for CVE-2026-20127 in the last 30 days.
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Coverage
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