CVE-2026-102866: Microsoft Office SharePoint Elevation of Privilege Vulnerability
Improper verification of cryptographic signature in Microsoft Office SharePoint allows an unauthorized attacker to elevate privileges over a network.
- Published by source
- 2026-10-13
- First seen by Reality Radar
- 2026-10-22
- Last verified
- 2026-10-22
Affected
- Manufacturer
- Microsoft
- Products
- Microsoft SharePoint Server Subscription Edition
- CPE
- cpe:2.3:a:microsoft:sharepoint_server:-:*:*:*:subscription:*:*:*
Whether your exact unit is affected depends on the model, serial number and region in the official notice.
What the official notice says
Risk: Critical — Elevation of Privilege
Remedy / actions:
- Install the security update: https://support.microsoft.com/help/5002927
Is this affecting you?
Add what you own or use and Reality Radar will tell you when official changes match it — with evidence and next steps.
Sources
- Microsoft Security Update Guide (MSRC) Tier A · official published 2026-10-13
Evidence ledger
Every piece of evidence we store is appended to a public hash chain, so later edits are detectable. Anyone can re-verify it.
| Entry | Kind | Observed | Evidence hash | Entry hash |
|---|---|---|---|---|
| #102 | new | 2026-10-22 | 8dc069600f25…33c9e7 | e4d1899f72b1…698618 |
Chain head: #1076 8ad5adc30b9b…88ce20