Skip to the content
The Update Bureau
Office Online Server OOS Office Online Server Security update
Patch Tuesday

KB5002928

KB5002928: Cumulative update for Office Online Server, version OOS, October 2026. Excel remote code execution vulnerabilities addressed before support ends

In short

Addresses 44 vulnerabilities, including 13 critical Excel remote code execution vulnerabilities. Updates for all Office Online Server editions end December 31, 2026.

Does it affect you? Applies to: Office Online Server installations running the release version. The standalone update package is for x64.

Build
16.0.10417.20228
Security
44 fixed · 13 critical
Restart
Required

What changes

Fix 1 change

Microsoft Excel

For: Office Online Server administrators

  • The update addresses Excel remote code execution and information disclosure vulnerabilities.1

Technical details

Data sheet · Security · Downloads · Components Click to collapse or expand

Data sheet

Released
2026-10-13
Classification
Security Updates
Type
Cumulative update
Restart
Required
Replaces
KB5002910, KB5002895, KB5002884, KB5002875
+20 earlier KB5002871, KB5002855, KB5002846, KB5002835, KB5002824, KB5002817, KB5002801, KB5002797, KB5002776, KB5002752, KB5002740, KB5002728, KB5002707, KB5002699, KB5002690, KB5002679, KB5002677, KB5002648, KB5002601, KB5002503
Replaced by
KB5002946
VersionBuildChannel
OOS 16.0.10417.20228 General availability

Security

44 vulnerabilities fixed
13 critical 31 important
VulnerabilitySeverityCVSS
CVE-2026-100210
Microsoft Office Excel Remote Code Execution Vulnerability
 Critical 8.8
CVE-2026-105718
Microsoft Excel Remote Code Execution Vulnerability
 Critical 8.8
CVE-2026-97739
Microsoft Office Excel Remote Code Execution Vulnerability
 Critical 8.8
CVE-2026-97742
Microsoft Office Excel Remote Code Execution Vulnerability
 Critical 8.8
CVE-2026-97753
Microsoft Office Excel Remote Code Execution Vulnerability
 Critical 8.8
CVE-2026-97755
Microsoft Office Excel Remote Code Execution Vulnerability
 Critical 8.8
CVE-2026-97756
Microsoft Office Excel Remote Code Execution Vulnerability
 Critical 8.8
CVE-2026-97758
Microsoft Office Excel Remote Code Execution Vulnerability
 Critical 8.8
CVE-2026-97765
Microsoft Office Excel Remote Code Execution Vulnerability
 Critical 8.8
CVE-2026-97767
Microsoft Office Excel Remote Code Execution Vulnerability
 Critical 8.8
CVE-2026-97776
Microsoft Office Excel Remote Code Execution Vulnerability
 Critical 8.8
CVE-2026-97778
Microsoft Office Excel Remote Code Execution Vulnerability
 Critical 8.8
CVE-2026-97780
Microsoft Office Excel Remote Code Execution Vulnerability
 Critical 8.8

The table lists the 13 exploited, publicly disclosed or critical vulnerabilities. See all 44 vulnerabilities →

Downloads (Microsoft Update Catalog)

Package OOS
1.0 GB
wacserver-x-none.cab Main update · KB5002928 SHA-1: 19bfcbb8…8d3050

Page history

  1. Superseded by KB5002946

Sources

Updated
Cited passages from Microsoft's official notes (1)
  1. 1. This security update resolves Microsoft Excel remote code execution vulnerability and Microsoft Excel Information Disclosure vulnerability. support.microsoft.com
Checked automatically: 7 of 8 checks passed, 1 quoted passage · compared with Microsoft's page on Nov 14, 2026
  • Quotes found in the official pages: passed
  • Numbers found in the sources: passed
  • Vulnerabilities from the dossier only: passed
  • Links to allowed domains only: passed
  • Every official change covered: passed
  • Readable plain text: passed
  • Changes confirmed by the file list: passed
  • Sources agree: not passed

A second AI read the text against the sources: correctness 4/5, clarity 4/5, completeness 5/5. How we work

Published by The Update Bureau. Written with AI from Microsoft's own documents, checked by rules and a second AI. How we work · Report a mistake