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Fencer Intel
critical 10.0

CVE-2026-20127 kev in the critical feed json

Cisco Catalyst SD-WAN Controller Authentication Bypass Vulnerability

published 8mo ago modified 4mo ago also EUVD-2026-8675

cvss
10.0
version 3.1, CNA
cisa kev
Exploited
added 2026-02-25
epss
87.6%
EPSS 87.6% chance of exploitation in 30 days, percentile 99.7%
public exploits
1
Metasploit

Summary

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. 

Patch / fix

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.

  • cisco catalyst_sd-wan_manager 20.9.8.2, 20.12.5.3, 20.15.4.2, 20.18.2.1
  • cisco sd-wan_vbond_orchestrator 20.9.8.2, 20.12.5.3, 20.15.4.2, 20.18.2.1
  • cisco sd-wan_vsmart_controller 20.9.8.2, 20.12.5.3, 20.15.4.2, 20.18.2.1

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Timeline

  1. First public exploit (Metasploit auxiliary/admin/networking/cisco_sdwan_auth_bypass)
  2. Added to CISA KEV
  3. Published
  4. CISA SSVC: exploitation active
  5. CISA patch deadline

Known exploited

Added
8mo ago
Patch by
2026-02-27 (8mo ago)
Ransomware
Not known
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.
Vendor, product
Cisco, Catalyst SD-WAN Controller and Manager
CISA name
Cisco Catalyst SD-WAN Controller and Manager Authentication Bypass Vulnerability

CISA SSVC

Exploitation
Active, exploited in the wild
Automatable
yes
Technical impact
total
Assessed
8mo ago

Exploit prediction

87.62% chance of exploitation in the next 30 days, higher than 99.7% of all scored CVEs (FIRST EPSS, 2026-11-09).

Exploits and checks

CVSS scores

assigned by version score vector
CNA 3.1 10.0 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
NVD 3.1 10.0 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H

Affected products

  • Cisco Cisco Catalyst SD-WAN Manager

Classification

Weakness

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.