---
cve: "CVE-2026-34908"
severity: "CRITICAL"
cvss: 10.0
epss: "88.9%"
vendor: "Ubiquiti Inc"
kev: true
exploited: true
published: "2026-05-22 02:16:34"
tags: [cve, security, critical]
source: tsecurity.de CVE-Dossier
exported: "2026-11-09T01:29:10+01:00"
---

# CVE-2026-34908

> 10.0 CRITICAL · ⚠️ CISA KEV (139 Tage) · 🔓 Exploited

## Beschreibung

A malicious actor with access to the network could exploit an Improper Access Control vulnerability found in UniFi OS devices to make unauthorized changes to the system.

## CNA-Record (Kanon, cvelistV5)

- CNA: **hackerone**
- State: PUBLISHED
- Stand: 2026-06-24 03:55:50
- 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: **23.06.2026**
- 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 |

## Schwachstellen-Klasse

- **CWE-284** — Improper Access Control
  The product does not restrict or incorrectly restricts access to a resource from an unauthorized actor.

## Angriffsmuster (CAPEC)

- [CAPEC-19 — Embedding Scripts within Scripts](https://capec.mitre.org/data/definitions/19.html) _(Severity: High)_
- [CAPEC-441 — Malicious Logic Insertion](https://capec.mitre.org/data/definitions/441.html) _(Severity: High)_
- [CAPEC-478 — Modification of Windows Service Configuration](https://capec.mitre.org/data/definitions/478.html) _(Severity: High)_
- [CAPEC-479 — Malicious Root Certificate](https://capec.mitre.org/data/definitions/479.html) _(Severity: Low)_
- [CAPEC-502 — Intent Spoof](https://capec.mitre.org/data/definitions/502.html)
- [CAPEC-503 — WebView Exposure](https://capec.mitre.org/data/definitions/503.html)
- [CAPEC-536 — Data Injected During Configuration](https://capec.mitre.org/data/definitions/536.html) _(Severity: High)_
- [CAPEC-546 — Incomplete Data Deletion in a Multi-Tenant Environment](https://capec.mitre.org/data/definitions/546.html) _(Severity: Medium)_

## ATT&CK-Techniken

- [T1027.009 — Obfuscated Files or Information: Embedded Payloads](https://attack.mitre.org/techniques/T1027/009/)
- [T1546.004 — Event Triggered Execution:.bash_profile and .bashrc](https://attack.mitre.org/techniques/T1546/004/)
- [T1546.016 — Event Triggered Execution: Installer Packages](https://attack.mitre.org/techniques/T1546/016/)
- [T1574.011 — Hijack Execution Flow:Service Registry Permissions Weakness](https://attack.mitre.org/techniques/T1574/011/)
- [T1543.003 — Create or Modify System Process:Windows Service](https://attack.mitre.org/techniques/T1543/003/)
- [T1553.004 — Subvert Trust Controls:Install Root Certificate](https://attack.mitre.org/techniques/T1553/004/)

## BSI-Hinweise (deutsch)

- [Ubiquiti UniFi OS Server: Mehrere Schwachstellen](https://wid.cert-bund.de/portal/wid/sicherheitshinweis/WID-SEC-W-2026-1639) — _BSI-Einstufung: kritisch_
  Ein Angreifer kann mehrere Schwachstellen in Ubiquiti UniFi OS Server ausnutzen, um beliebigen Programmcode auszuführen, Sicherheitsmaßnahmen zu umgehen, Daten zu manipulieren oder vertrauliche Informationen offenzulegen.

## Referenzen

- <https://community.ui.com/releases/Security-Advisory-Bulletin-064-064/84811c09-4cf4-42ab-bd61-cc994445963b>
- <https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-34908>
- <https://www.pwndefend.com/2026/06/09/cve-2026-34910-exploitation-itw-building-a-botnet-mirai/>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/sicherheitsluecken/cve-2026-34908/) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI WID (CSAF)_