Patch tracker / KB5081276
KB5081276: Microsoft.Bcl.Memory 10.0 Security Update (March 2026)
KB5081276 is a High security update for Microsoft.Bcl.Memory 10.0, released 2026-03-10. It closes 3 CVEs with a maximum CVSS of 7.8. It is the 18th largest of the 43 updates Microsoft shipped that month, by CVEs closed.
Update summary
Fixes 3 CVEs. Most severe CVSS 7.8 (High). EPSS exploit probability up to 2.8%. Among the top half of tracked Microsoft updates by EPSS exploit probability.
A newer security update for .NET 10.0 installed on Linux has shipped since this one: KB5122104 (2026-08-11). 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.
KB5081276 patches three CVEs in .NET 10.0 across both Linux and Windows installs, plus the Microsoft.Bcl.Memory 10.0 package, with the worst rated High severity at CVSS 7.8. Because it spans cross-platform .NET runtimes, both your Windows servers and Linux-hosted .NET workloads are exposed, not just one side of the estate. None of the three CVEs are in CISA KEV or linked to ransomware, and EPSS peaks at only 3 percent, so this is a patch-on-schedule item rather than an emergency.
Do this: Inventory both Windows and Linux hosts running .NET 10.0 and update the runtime and any bundled Microsoft.Bcl.Memory 10.0 dependencies to the KB5081276 build.
AI-generated from public data, 2026-07-21. Verify against the vendor advisory before acting.
Senserva AI Opinion and rich prompt for KB5081276
Copy this prompt into Claude, ChatGPT, or Copilot. The facts are included, sourced from this page.
Full tracking and change history for KB5081276
- Released
- 2026-03-10
- Last changed
- 2026-03-10
- Changes tracked
- 1
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 KB5081276 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.
| CVE | Severity | CVSS | EPSS | Exploited |
|---|---|---|---|---|
| CVE-2026-26131 | High | 7.8 | 2.8% | No |
| CVE-2026-26127 | High | 7.5 | 2.8% | No |
| CVE-2026-26130 | High | 7.5 | 2.8% | No |
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.