🟠 High | Source: Microsoft Security Response Center
A cross-site scripting (XSS) vulnerability in Microsoft SharePoint Server allows an authenticated attacker to perform spoofing attacks over a network by injecting malicious content into web pages generated by the application. Because the attacker only needs to be an authorised user rather than an administrator, the barrier to exploitation is relatively low. This is particularly concerning in organisations where SharePoint is widely used for internal collaboration and document management.
Security Architect’s Take: Prioritise applying the relevant Microsoft patch immediately, especially for internet-facing or externally accessible SharePoint deployments. In the interim, consider restricting SharePoint access to trusted networks via conditional access policies or network controls, and review audit logs for any suspicious authenticated activity.
Original advisory: CVE-2026-62829 Microsoft SharePoint Server Spoofing Vulnerability