Patch tracker / KB5101000
KB5101000: .NET 8.0 installed on Mac OS Security Update (July 2026)
KB5101000 is a High security update for .NET 8.0 installed on Mac OS, released 2026-07-14. It closes 17 CVEs with a maximum CVSS of 8.1. The most likely of them to be attacked is CVE-2026-47302, which FIRST.org rates at 64% probability of exploitation in the next 30 days.
Update summary
Fixes 17 CVEs. Most severe CVSS 8.1 (High). EPSS exploit probability up to 1.1%. Among the lower half of tracked Microsoft updates by EPSS exploit probability.
Microsoft documents 1 known issue with this update.
- Microsoft is not currently aware of any issues in this update.
KB5101000 is a Security Update bundling .NET Framework 3.5 and 4.8.1 fixes for Windows 10 versions 21H2 and 22H2 across 32-bit, x64, and ARM64 systems. The per-update CVE detail for July 2026 is still provisional and not yet published by Microsoft, and the release document maps no named zero-days to this specific update. Because it touches both the legacy 3.5 runtime and 4.8.1 on the same machines, any application still bound to the older framework is in scope alongside modern ones.
Do this: Stage KB5101000 to a pilot ring covering both 21H2 and 22H2 endpoints and confirm .NET 3.5 dependent applications still start before broad deployment.
AI-generated from public data, 2026-07-21. Verify against the vendor advisory before acting.
Senserva AI Opinion and rich prompt for KB5101000
Copy this prompt into Claude, ChatGPT, or Copilot. The facts are included, sourced from this page.
Full tracking and change history for KB5101000
- Released
- 2026-07-14
- 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 KB5101000 is installed
Elevated PowerShell. No output means it is not installed.
Known issues, from Microsoft
Quoted from Microsoft's support article for KB5101000 (checked 2026-08-12). Verify against the article before acting.
Microsoft is not currently aware of any issues in this update.
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-2026-47304 | High | 8.1 | 64% | No |
| CVE-2026-50646 | High | 7.8 | 64% | No |
| CVE-2026-50649 | High | 7.8 | 64% | No |
| CVE-2026-50650 | High | 7.8 | 64% | No |
| CVE-2026-47302 | High | 7.5 | 64% | No |
| CVE-2026-50304 | High | 7.5 | 64% | No |
| CVE-2026-50355 | High | 7.5 | 64% | No |
| CVE-2026-50368 | High | 7.5 | 64% | No |
| CVE-2026-50411 | High | 7.5 | 64% | No |
| CVE-2026-50525 | High | 7.5 | 64% | No |
| CVE-2026-50527 | High | 7.5 | 64% | No |
| CVE-2026-50647 | High | 7.5 | 64% | No |
| CVE-2026-50648 | High | 7.5 | 64% | No |
| CVE-2026-50652 | High | 7.5 | 64% | No |
| CVE-2026-50653 | High | 7.5 | 64% | No |
| CVE-2026-50659 | Medium | 6.5 | 64% | No |
| CVE-2026-50324 | Medium | 5.9 | 64% | No |
Scope and sources
- Affected products
- Also released in July 2026
KB5099444
185 CVEs · Critical · exploitedKB5099445
174 CVEs · Critical · exploitedKB5099535
261 CVEs · Critical · exploitedKB5099536
389 CVEs · Critical · exploitedKB5099538
312 CVEs · Critical · exploitedKB5099539
314 CVEs · Critical · exploitedKB5099540
326 CVEs · Critical · exploitedKB5101649
383 CVEs · Critical · exploitedThe full month, summarized: Microsoft Patch Tuesday.
- Authoritative references
See this and every Microsoft update ranked by real-world risk on the Microsoft Patch Tracker.