Researchers Disclose AI-Assisted SharePoint Exploit Chain Reaching Unauthenticated RCE
A CVSS 9.1 unauthenticated RCE chain in SharePoint Server (CVE-2026-55040), partly discovered by an AI agent, demands emergency patching—especially for on-prem deployments common in European enterprise.
Summary written by editorial AI · Source link below
Security researchers found a way to enter Microsoft SharePoint servers as any user, including an administrator, with no valid account. A significant part of the work that found it was done through an AI agent.
The flaw, tracked as CVE-2026-55040 (CVSS 9.1), affects SharePoint Server Subscription Edition, SharePoint Server 2019, and SharePoint Server 2016. Microsoft's
Editorial Analysis
On-premises SharePoint remains a backbone of European enterprise collaboration; an unauthenticated RCE at CVSS 9.1 puts document repositories, intranet portals, and connected workflows at immediate risk.
Emergency-patch all SharePoint Server Subscription Edition instances and restrict network exposure of unpatched servers pending remediation.
A critical unauthenticated vulnerability in Microsoft SharePoint Server could allow full system takeover without credentials—immediate patching is required.
Forward-looking interpretation drafted by editorial AI under human review — not a reproduction of the source. See methodology.
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