Patch tracker / CVE reference / CVE-2026-44818
CVE-2026-44818
CVE-2026-44818 is a high severity Microsoft vulnerability with a CVSS score of 7.0. Microsoft has shipped the fix: deploy one of the 2 updates below from the Microsoft Update Catalog, and see where this CVE sits against the rest on the patch tracker.
Risk summary
Not in the CISA KEV catalog. EPSS exploit probability <1%. CVSS 7.0 (High).
This CVE is among the lower half of tracked Microsoft CVEs by EPSS exploit probability.
CVE-2026-44818 is a remote code execution flaw in Microsoft Excel that spans an unusual mix of platforms: Office 365 for Mac, Office Online Server, and Office 2019 32-bit. Because Office Online Server processes documents on shared infrastructure, a malicious spreadsheet could execute code in a server context rather than just on a single user machine. Severity is rated High with a CVSS of 8.2, though EPSS exploit probability is only 1 percent and it is not in CISA KEV nor linked to ransomware.
Do this: Prioritize patching Office Online Server first since it processes attacker-supplied files server-side, then push the Excel updates to Mac and 32-bit Office 2019 endpoints.
AI-generated from public data, 2026-07-21. Verify against the vendor advisory before acting.
Senserva AI Opinion and rich prompt for CVE-2026-44818
Copy this prompt into Claude, ChatGPT, or Copilot. The facts are included, sourced from this page.
Official patch(es) for CVE-2026-44818
Moderate priority: schedule it in your normal patch cycle. In Intune or Defender, confirm whether the fixing updates KB5002875, KB5002877 are installed across the affected products. Senserva does this automatically across your tenant and flags every missing patch.
Apply the Microsoft security updates below to fix CVE-2026-44818. 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
- Fixed by the same updates
- Authoritative references
Want every Microsoft CVE and the patches that fix it, ranked by real-world risk? See the Microsoft Patch Tracker.