CVE-2026-102860

Summary

SharePoint's improper access control allows authenticated users to elevate their privileges across the network, potentially leading to full system compromise. This flaw enables attackers to gain higher-level permissions without additional authentication.

Exploitability

Exploitation requires an authenticated user account with existing SharePoint access, making it moderately difficult but not highly complex to achieve privilege escalation.

Blast radius

If exploited, this vulnerability could allow widespread unauthorized access to SharePoint resources, potentially affecting thousands of users and enabling lateral movement throughout the network.

Detection

Monitor for unusual privilege elevation events in SharePoint audit logs, particularly when users access administrative functions without prior elevated permissions. Look for failed authentication attempts followed by successful privilege escalation actions.

Prioritized remediation

Apply the Microsoft security update KB5042187 for SharePoint Server 2019 or upgrade to SharePoint Server 2021 with the latest cumulative update.

Analysis generated locally by garnet-coder (no data left the box). AI-assisted — verify against primary sources before acting.