Patch tracker / KB5078885
KB5078885: Windows 10 Version 1809 for 32-bit Sys Security Update (March 2026)
KB5078885 is a High security update for Windows 10 Version 1809 for 32-bit Sys, released 2026-03-10. It closes 43 CVEs with a maximum CVSS of 8.8. It is the largest of the 38 updates Microsoft shipped that month, by CVEs closed.
Update summary
Fixes 43 CVEs. Most severe CVSS 8.8 (High). EPSS exploit probability up to 4.7%. Among the top half of tracked Microsoft updates by EPSS exploit probability.
A newer security update for Windows 10 Version 1809 for 32-bit Systems has shipped since this one: KB5089548 (2026-07-14). For cumulative update families the newer package includes these fixes, so installing that one is usually the shorter path. Verify against your own update rings before you skip this package.
KB5078885 is a March 2026 rollup for Windows 10 1809 and 21H2 that patches 43 CVEs, with the worst rated High at CVSS 8.8. None are in the CISA KEV catalog or linked to ransomware, and the highest EPSS is only 4 percent, so this is a large but not actively exploited batch affecting legacy and current Windows 10 endpoints. The volume matters because 1809 is an aging branch and each unpatched host carries the full set of 43 fixes.
Do this: Deploy KB5078885 to all Windows 10 1809 and 21H2 systems this cycle, prioritizing internet-facing and shared machines.
AI-generated from public data, 2026-07-21. Verify against the vendor advisory before acting.
Senserva AI Opinion and rich prompt for KB5078885
Copy this prompt into Claude, ChatGPT, or Copilot. The facts are included, sourced from this page.
Full tracking and change history for KB5078885
- Released
- 2026-03-10
- Last changed
- 2026-07-24
- Changes tracked
- 2
Senserva began recording day-to-day change history on 2026-07-07, and refreshes it several times a day. Release dates are historical where Microsoft publishes them; revision history is tracked from that date forward, so it does not include changes made before then.
Check if KB5078885 is installed
Elevated PowerShell. No output means it is not installed.
CVEs fixed by this update
Sorted exploited-first, then by CVSS. Every CVE links to its Senserva page with the full risk facts, references, and a ready-to-paste AI prompt.
Scope and sources
- Affected products
- Also released in March 2026
KB5002843
3 CVEs · HighKB5002845
4 CVEs · HighKB5002850
4 CVEs · HighKB5077464
2 CVEs · HighKB5077465
2 CVEs · HighKB5077466
3 CVEs · HighKB5077468
3 CVEs · HighKB5077469
2 CVEs · HighThe full month, summarized: Microsoft Patch Tuesday.
- Authoritative references
See this and every Microsoft update ranked by real-world risk on the Microsoft Patch Tracker.