---
cve: "CVE-2025-20309"
severity: "CRITICAL"
cvss: 10.0
epss: "1.1%"
vendor: "Cisco"
kev: false
exploited: false
published: "2025-07-02 17:15:52"
tags: [cve, security, critical]
source: tsecurity.de CVE-Dossier
exported: "2026-10-24T20:42:05+02:00"
---

# CVE-2025-20309

> 10.0 CRITICAL

## Beschreibung

A vulnerability in Cisco Unified Communications Manager (Unified CM) and Cisco Unified Communications Manager Session Management Edition (Unified CM SME) could allow an unauthenticated, remote attacker to log in to an affected device using the root account, which has default, static credentials that cannot be changed or deleted.

This vulnerability is due to the presence of static user credentials for the root account that are reserved for use during development. An attacker could exploit this vulnerability by using the account to log in to an affected system. A successful exploit could allow the attacker to log in to the affected system and execute arbitrary commands as the root user.

## CNA-Record (Kanon, cvelistV5)

- CNA: **cisco**
- State: PUBLISHED
- Stand: 2026-02-26 18:27:57
- 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-SSVC (Coordinator, v2.0.3):
  - Exploitation: **none**
  - 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 Unified Communications Manager (CUCM): Schwachstelle ermöglicht Erlangen von Administratorrechten](https://wid.cert-bund.de/portal/wid/sicherheitshinweis/WID-SEC-W-2025-1448) — _BSI-Einstufung: hoch_
  Ein entfernter, anonymer Angreifer kann eine Schwachstelle in Cisco Unified Communications Manager (CUCM) ausnutzen, um Administratorrechte zu erlangen.

## Referenzen

- <https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-cucm-ssh-m4UBdpE7>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/sicherheitsluecken/cve-2025-20309/) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI WID (CSAF)_