CVE-2026-123391: Microsoft Office SharePoint privilege escalation via incorrect authorization

CVE-2026-123391 · Severity: high · CVSS 8.8 · Published 2026-11-10

Microsoft Office SharePoint, a document management and team collaboration platform used by many organizations, contains an authorization flaw that allows an already-authenticated user to elevate their privileges beyond what they should have access to. An attacker with valid SharePoint credentials could exploit this to gain admin-level access and compromise sensitive documents and data across the organization.

Technologies: Microsoft Office SharePoint. Vendors: Microsoft.

Quick answers

Is CVE-2026-123391 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-123391 being exploited in the wild.
How severe is CVE-2026-123391?
High severity, with a CVSS score of 8.8, published 10 November 2026.
Which products and versions are affected?
Microsoft Office SharePoint.
Is there a fix for CVE-2026-123391?
No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
How is CVE-2026-123391 attacked?
It is attacked over the network.
Am I affected by CVE-2026-123391?
Check whether you run Microsoft Office SharePoint. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

An incorrect authorization check in Microsoft Office SharePoint allows a network-authenticated attacker to escalate privileges. The vulnerability requires the attacker to be an authorized user with existing credentials, and can be exploited remotely over the network. Successful exploitation grants the attacker elevated permissions within SharePoint.

Affected products

  • Microsoft Office SharePoint

Timeline

  • 2026-11-10: disclosed

References

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