Patch tracker / KB5082403
KB5082403: .NET 8.0 Security Update (April 2026)
KB5082403 is a High security update for .NET 8.0, released 2026-04-14. It closes 3 CVEs with a maximum CVSS of 7.5. Get it from the Microsoft Update Catalog below, and see where it sits against the rest of the month on the patch tracker.
Update summary
New to these terms? How the Microsoft patching tools fit together, this month's Patch Tuesday summary, and every update ranked by real-world risk.
Senserva AI Opinion for KB5082403
KB5082403 patches three CVEs across .NET 10.0 on macOS and Linux plus .NET 8.0, with the worst rated High severity at CVSS 7.5 and a denial of service style profile rather than remote code execution. Exposure is unusual here because it spans your cross platform .NET runtimes, so Mac and Linux build agents and containers are in scope, not just Windows. EPSS is only 2 percent and none of the three CVEs are in CISA KEV or linked to ransomware, so this is a plan and schedule item rather than an emergency.
Do this: Inventory every .NET 10.0 (macOS and Linux) and .NET 8.0 runtime and SDK across your servers, containers, and CI agents, then roll out KB5082403 to those hosts.
AI-generated from public data, 2026-07-21. Verify against the vendor advisory before acting.
Senserva AI Opinion and rich prompt for KB5082403
Copy this prompt into Claude, ChatGPT, or Copilot. The facts are included, sourced from this page.
Full tracking and change history for KB5082403
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.
Exploitation and severity
Fixes 3 CVEs. Most severe CVSS 7.5 (High). EPSS exploit probability up to 2.1%.
Among the lower half of tracked Microsoft updates by EPSS exploit probability.
What to do
Moderate priority: schedule it in your normal patch cycle. Senserva flags whether KB5082403 is missing on your devices.
Check if KB5082403 is installed
Copy-paste PowerShell: one machine, or your whole estate in one pass. No output means the update is not installed.
Get-HotFix covers Windows updates. Office, SharePoint, and Exchange server updates show under installed updates in Programs and Features, or check the Update Catalog history.
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-2026-23666 | High | 7.5 | 2.1% | No |
| CVE-2026-32226 | High | 7.5 | 2.1% | No |
| CVE-2026-33116 | High | 7.5 | 2.3% | No |
Affected products
Also released in April 2026
The highest-risk updates from the same release:
The full month, summarized: Microsoft Patch Tuesday.
Authoritative references
See this and every Microsoft update ranked by real-world risk on the Microsoft Patch Tracker.