Cybersecurity
Microsoft Office SharePoint spoofing flaw allows authorized attacker to inject content via web page generation
Microsoft reports CVE-2026-102859, a spoofing vulnerability in Microsoft Office SharePoint caused by insufficient sanitization before web page rendering. The advisory describes it as a cross-site scripting weakness that an authorized attacker can exploit over a network. Defenders should apply vendor fixes, review SharePoint access controls, and monitor authenticated sessions for anomalous rendered content.
What happened
Microsoft reported CVE-2026-102859, a spoofing vulnerability in Microsoft Office SharePoint caused by insufficient sanitization before web page rendering. The advisory describes it as a cross-site scripting weakness that an authorized attacker can exploit over a network.
Impact
An authenticated attacker may inject content into generated web pages, potentially misleading users or facilitating further attacks.
Recommended actions
- Apply vendor fixes or mitigations as released.
- Review SharePoint access controls and user permissions.
- Monitor authenticated sessions and rendered content for anomalies.
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