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CVE-2026-20127

Cisco Catalyst SD-WAN Controller Authentication Bypass Vulnerability

Published: Feb 25, 2026Updated: Feb 26, 2026 Sources: CVE List NVD BDU
10.0CVSS
CRITICAL

A vulnerability in the peering authentication in Cisco Catalyst SD-WAN Controller, formerly SD-WAN vSmart, and Cisco Catalyst SD-WAN Manager, formerly SD-WAN vManage, 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. 

EPSS Score
54.8%
Top 1.9%
CISA KEV
Active Exploitation
Since Feb 25, 2026
Exploits
0 Known
Remediation
Patch Available

CVSS Vector Breakdown

AV:NAC:LPR:NUI:NS:CC:HI:HA:H
Exploitability
AV:NAttack Vector
Network
AC:LAttack Complexity
Low
PR:NPrivileges Required
None
UI:NUser Interaction
None
Scope
S:CScope
Changed
Impact
C:HConfidentiality
High
I:HIntegrity
High
A:HAvailability
High

Weaknesses

Affected Products

catalyst sd-wan manager
cisco
sd-wan vsmart controller
cisco
Catalyst SD-WAN Manager
Cisco Systems Inc.
Cisco Catalyst SD-WAN Controller
Cisco Systems Inc.
Cisco Catalyst SD-WAN Manager
Cisco

Attack Graph

Products CVE Techniques Tactics

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Exploitability

CISA Known Exploited Vulnerability
Added to KEV:Feb 25, 2026
Remediation due:Feb 27, 2026

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.

0 exploit sources identified

Exploit details including PoC links, Metasploit modules, and scanner templates are available after registration.

View exploit details
Official Patch Available

MITRE ATT&CK

2 techniques
Initial Access
View detailed technique mapping

References

Timeline

Added to CISA KEV
Feb 25, 2026
Published
Feb 25, 2026
Last Updated
Feb 26, 2026
6

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