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Vulnerability Intelligence

CVE-2026-20127

CriticalExploitedPublic exploit

Cisco Catalyst SD-WAN Controller Authentication Bypass Vulnerability

Published Feb 25, 2026 · Updated Jun 17, 2026

Key Facts

Patch immediately
  • CVE-2026-20127 is a critical-severity vulnerability (CVSS 10.0 v3.1) affecting Catalyst SD-WAN Manager (Cisco), SD-WAN Vbond Orchestrator (Cisco), SD-WAN Vsmart Controller (Cisco).
  • It is exploited in the wild, listed in CISA KEV, Industry KEV feed, CIRCL KEV, ENISA EUVD since Feb 25, 2026. Public exploit code is available.
  • EPSS estimates a 88% probability of exploitation in the next 30 days.
  • Fixed versions are available, including Catalyst SD-WAN Manager 20.12.5.3, Catalyst SD-WAN Manager 20.15.4.2, Catalyst SD-WAN Manager 20.18.2.1.
  • Brandefense priority: patch immediately, because it is listed as exploited in the wild.

CVSS v3.1

10.0

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H

EPSS (30-day exploit likelihood)

88%

Higher than 99.7% of all scored CVEs

Exploited in the wild

Yes

4 catalog listings

Public exploit code

Available

Proof-of-concept or weaponized module

Get the full CVE-2026-20127 brief as a PDF

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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.

Known-Exploited Catalog Listings

CatalogAddedRemediation dueRansomware use
CISA KEVFeb 25, 2026Feb 27, 2026Not reported
Industry KEV feedFeb 25, 2026Feb 27, 2026Not reported
CIRCL KEVFeb 25, 2026Feb 27, 2026Not reported
ENISA EUVDFeb 25, 2026n/aNot reported

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.

Affected Products

7 affected entries in total
ProductAffected versionsFixed in
Catalyst SD-WAN ManagerCisco20.12.6, >= 20.1.1220.9.8.2
SD-WAN Vbond OrchestratorCisco20.12.620.9.8.2
SD-WAN Vsmart ControllerCisco20.12.620.9.8.2

Patched Releases

Catalyst SD-WAN Manager

20.12.5.3, 20.15.4.2, 20.18.2.1, 20.9.8.2

SD-WAN Vbond Orchestrator

20.12.5.3, 20.15.4.2, 20.18.2.1, 20.9.8.2

SD-WAN Vsmart Controller

20.12.5.3, 20.15.4.2, 20.18.2.1, 20.9.8.2

Timeline

  1. Publicly disclosed

    Feb 25, 2026

  2. Added to CISA KEV

    Feb 25, 2026

  3. Added to Industry KEV feed

    Feb 25, 2026

  4. Added to CIRCL KEV

    Feb 25, 2026

  5. Added to ENISA EUVD

    Feb 25, 2026

  6. Last updated

    Jun 17, 2026

Weakness Type

  • CWE-287 Improper Authentication

References

5 more references in the full CVE brief

FAQ

Common Questions.

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