Patch tracker / CVE reference / CVE-2026-100210
CVE-2026-100210
CVE-2026-100210 is a Microsoft vulnerability that Microsoft rates Critical, with a CVSS score of 8.8 (High). Microsoft has shipped the fix: deploy the update below from the Microsoft Update Catalog, and see where this CVE sits against the rest on the patch tracker.
Our data comes from Microsoft, CISA and other public sources, and it can be wrong or out of date. If you are unsure, check the linked source before you act, and tell us when we are wrong so we can fix it.
Microsoft rates it Critical. CVSS 8.8 (High). Fixed by 1 Microsoft security update.
Risk summary
Not in the CISA KEV catalog. EPSS exploit probability <1%. CVSS 8.8 (High).
This CVE is among the top 25% of tracked Microsoft CVEs by EPSS exploit probability.
CVE-2026-100210 is a remote code execution flaw in Microsoft Excel that affects volume-licensed Office LTSC 2021 (both 32-bit and 64-bit) and Office LTSC 2024 64-bit, the perpetual-license builds often found on locked-down or air-gapped desktops. Severity is High (CVSS 8.8), but exploitation pressure is low right now: EPSS puts exploit probability at 1%, it is not in CISA KEV, and there is no known ransomware use. Because the bug sits in a spreadsheet application, the practical risk is a user opening a crafted file, so exposure concentrates on finance, analyst, and shared-mailbox workflows that handle externally sourced workbooks.
Do this: Inventory which endpoints run Office LTSC 2021 or LTSC 2024 and deploy the Microsoft fix for this CVE to them first, prioritizing users who routinely open Excel files from outside the organization.
AI-generated from public data, 2026-11-10. Verify against the vendor advisory before acting.
Senserva AI Opinion and rich prompt for CVE-2026-100210
Copy this prompt into Claude, ChatGPT, or Copilot. The facts are included, sourced from this page.
Official patch(es) for CVE-2026-100210
Moderate priority: schedule it in your normal patch cycle. In Intune or Defender, confirm whether the fixing update KB5002928 are installed across the affected products. Senserva does this automatically across your tenant and flags every missing patch.
Apply the Microsoft security update below to fix CVE-2026-100210. Each KB page carries the Microsoft Update Catalog download, Microsoft's known issues for the update, a copy-paste PowerShell check for whether it is installed, and the Senserva AI read.
Scope and sources
- Affected products
- Microsoft 365 Apps for Enterprise for 32-bit Systems
- Microsoft 365 Apps for Enterprise for 64-bit Systems
- Microsoft Office 365 for Mac
- Microsoft Office LTSC 2021 for 32-bit editions
- Microsoft Office LTSC 2021 for 64-bit editions
- Microsoft Office LTSC 2024 for 32-bit editions
- Microsoft Office LTSC 2024 for 64-bit editions
- Microsoft Office LTSC for Mac 2021
- Microsoft Office LTSC for Mac 2024
- Office Online Server
- Fixed by the same update
- Authoritative references
Want every Microsoft CVE and the patches that fix it, ranked by real-world risk? See the Microsoft Patch Tracker.