---
cve: "CVE-2026-20127"
severity: "CRITICAL"
cvss: 10.0
epss: "87.6%"
vendor: "Cisco"
kev: true
exploited: true
published: "2026-02-25 17:25:29"
tags: [cve, security, critical]
source: tsecurity.de CVE-Dossier
exported: "2026-11-09T11:32:39+01:00"
---

# CVE-2026-20127

> 10.0 CRITICAL · ⚠️ CISA KEV (257 Tage) · 🔓 Exploited

## Beschreibung

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. 

## CNA-Record (Kanon, cvelistV5)

- CNA: **cisco**
- State: PUBLISHED
- Stand: 2026-06-16 17:57:59
- CNA-CVSS: **10.0** (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H`)

## CISA-Anreicherung (vulnrichment/ADP)

- CISA KEV seit: **25.02.2026**
- CISA-SSVC (Coordinator, v2.0.3):
  - Exploitation: **active**
  - Automatable: **yes**
  - Technical Impact: **total**

## CVSS-Vektor

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

| Metrik | Wert | Bewertung |
|---|---|---|
| AV Angriffsvektor | Netzwerk | bad |
| AC Komplexität | Gering | bad |
| PR Privilegien | Keine | bad |
| UI Interaktion | Keine | bad |
| S Scope | Verändert | bad |
| C Vertraulichkeit | Hoch | bad |
| I Integrität | Hoch | bad |
| A Verfügbarkeit | Hoch | bad |

## BSI-Hinweise (deutsch)

- [Cisco Catalyst SD-WAN Manager und SD-WAN Controller: Mehrere Schwachstellen](https://wid.cert-bund.de/portal/wid/sicherheitshinweis/WID-SEC-W-2026-0516) — _BSI-Einstufung: kritisch_
  Ein entfernter, anonymer oder lokaler Angreifer kann mehrere Schwachstellen in Cisco Catalyst SD-WAN Manager ausnutzen, um Administratorrechte zu erlangen, die Authentifizierung zu umgehen, Befehle mit Netadmin-Rechten auszuführen, sensible Systeminformationen zu lesen und beliebige Dateien auf dem System zu überschreiben.

## Referenzen

- <https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-sdwan-rpa-EHchtZk>
- <https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-20127>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/sicherheitsluecken/cve-2026-20127/) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI WID (CSAF)_