Collabora Online Built-in CODE Server (NextCloud): Schwachstelle ermöglicht Ausführen von beliebigem Programmcode mit Benutzerrechten
WID-SEC-2026-4011 · first 19.10.2026 · updated 19.10.2026 · CVSS 9,8
What it is about
Collabora Online ist eine LibreOffice-basierte Online-Office-Suite, die das gemeinsame Bearbeiten von Dokumenten direkt im Webbrowser ermöglicht. Ein entfernter, anonymer Angreifer kann eine Schwachstelle in Collabora Collabora Online ausnutzen, um beliebigen Programmcode als Webserver-Benutzer auszuführen.
Under what conditions?
Over the network and without logging in. This is the most dangerous combination: attackers can scan reachable devices automatically.
What can happen in the worst case
An attacker could use the vulnerability to
- beliebigen Programmcode als Webserver-Benutzer auszuführen
Am I affected?
Affected according to the BSI:
- Collabora Collabora Online Built-in CODE Server <26.4.303
The installed version is usually shown under “Help → About” or in the device’s admin interface.
What helps?
Update to at least:
- Collabora Collabora Online Built-in CODE Server 26.4.303
Is the vulnerability already being exploited?
None of the CVEs is in the CISA catalogue of exploited vulnerabilities. That does not mean there are no attacks, only that none are documented.
Information and sources
- Original BSI advisory (WID)
- Collabora Online Security Advisory vom 2026-10-18 github.com
- NextCloud Advisory vom 2026-10-18 help.nextcloud.com
CVE: CVE-2026-110447
Source: BSI warning and information service (CERT-Bund); CISA. The assessment of the conditions is my reading of the BSI text; the external pages are in their original language.