Patch tracker / CVE reference / CVE-2026-55045
CVE-2026-55045
CVE-2026-55045 is a Microsoft vulnerability that Microsoft rates Critical, with a CVSS score of 8.4 (High). Microsoft has shipped the fix: deploy one of the 6 updates below from the Microsoft Update Catalog, and see where this CVE sits against the rest on the patch tracker.
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Microsoft rates it Critical. CVSS 8.4 (High). Fixed by 6 Microsoft security updates.
Risk summary
Not in the CISA KEV catalog. EPSS exploit probability <1%. CVSS 8.4 (High).
This CVE is among the lower half of tracked Microsoft CVEs by EPSS exploit probability.
CVE-2026-55045 is a Critical (CVSS 9.8) remote code execution flaw spanning both on-premises SharePoint (Enterprise Server 2016 and Server 2019) and Microsoft 365 Apps for Enterprise on 32-bit systems, an unusually broad mix of server and client footprints. It is not yet in CISA KEV and has no known ransomware use, but the 57 percent EPSS score signals exploitation is more likely than not in the near term. SharePoint servers are typically internet-facing and hold sensitive business content, so a 9.8 RCE there is a direct path to full compromise.
Do this: Prioritize patching your SharePoint 2016 and 2019 servers first, then roll out the update to 32-bit Microsoft 365 Apps clients.
AI-generated from public data, 2026-07-26. Verify against the vendor advisory before acting.
Senserva AI Opinion and rich prompt for CVE-2026-55045
Copy this prompt into Claude, ChatGPT, or Copilot. The facts are included, sourced from this page.
Official patch(es) for CVE-2026-55045
Moderate priority: schedule it in your normal patch cycle. In Intune or Defender, confirm whether the fixing updates KB5002882, KB5002883, KB5002885, KB5002887, KB5002891, KB5002892 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-2026-55045. 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.