Microsoft SharePoint Online: Schwachstelle ermöglicht Cross-Site Scripting
WID-SEC-2026-2691 · first 07.08.2026 · updated 07.08.2026 · CVSS 9,6
What it is about
Microsoft Sharepoint Services ist ein Portalsystem für die zentrale Verwaltung von Dokumenten und Anwendungen. Die Inhalte werden u.a. über Webseiten zur Verfügung gestellt. Ein entfernter, anonymer Angreifer kann eine Schwachstelle in Microsoft SharePoint Online ausnutzen, um einen Cross-Site Scripting Angriff durchzuführen.
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
- einen Cross-Site Scripting Angriff durchzuführen
Am I affected?
Affected according to the BSI:
- Microsoft SharePoint Online
The installed version is usually shown under “Help → About” or in the device’s admin interface.
What helps?
Install the updates provided by the vendor; details in the sources below.
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)
- Microsoft Security Update Guide vom 2026-08-06 msrc.microsoft.com
CVE: CVE-2026-70332
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.