Patch tracker / KB5082200
KB5082200: Windows 10 Version 21H2 Security Update (April 2026)
KB5082200 is a Critical security update for Windows 10 Version 21H2, released 2026-04-14. It closes 106 CVEs with a maximum CVSS of 9.8. At least one of them is actively exploited (CISA KEV), so it is urgent, and Microsoft lists 1 known issue: test it before broad deployment. It is the seventh largest of the 60 updates Microsoft shipped that month, by CVEs closed.
Before you deploy: Microsoft lists 1 known issue for this update.
Our data comes from Microsoft, CISA and other public sources, and it can be wrong or out of date. If you are unsure, check the linked source before you act, and tell us when we are wrong so we can fix it.
Update summary
Fixes 106 CVEs. At least one is actively exploited (CISA KEV). Most severe CVSS 9.8 (Critical). EPSS exploit probability up to 3.5%. Among the top half of tracked Microsoft updates by EPSS exploit probability.
A newer security update for Windows 10 Version 21H2 for 32-bit Systems has shipped since this one: KB5126657 (2026-10-13). 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.
Microsoft documents 1 known issue with this update.
- Devices with an unrecommended BitLocker Group Policy configuration might be required to enter their BitLocker recovery key
KB5082200 is a large April 2026 rollup for Windows 10 Version 1809 and Windows Server 2019, closing 108 CVEs including one rated Critical at CVSS 9.8 with a 64 percent EPSS score. At least one of these CVEs is listed in the CISA Known Exploited Vulnerabilities catalog, so exposure is confirmed in the wild rather than theoretical, though none are currently tied to ransomware. Any 1809 or Server 2019 host that has not taken this cumulative update is missing all 108 fixes at once.
Do this: Deploy KB5082200 to all Windows 10 1809 and Windows Server 2019 systems now, prioritizing internet-facing Server 2019 hosts because of the confirmed KEV-listed and CVSS 9.8 vulnerabilities.
AI-generated from public data, 2026-07-21. Verify against the vendor advisory before acting.
Senserva AI Opinion and rich prompt for KB5082200
Copy this prompt into Claude, ChatGPT, or Copilot. The facts are included, sourced from this page.
Full tracking and change history for KB5082200
- Released
- 2026-04-14
- Last changed
- 2026-10-15
- Changes tracked
- 7
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.
- 2026-08-19 CVEs fixed 108 to 107
Recorded by Senserva on the dates shown, from the MSRC release feed. This is what moved and when, which neither the vendor advisory nor NVD publishes.
Check if KB5082200 is installed
Elevated PowerShell. No output means it is not installed.
Known issues, from Microsoft
Quoted from Microsoft's support article for KB5082200 (checked 2026-09-10). Microsoft lists 1 known issue. Verify against the article before acting.
Devices with an unrecommended BitLocker Group Policy configuration might be required to enter their BitLocker recovery key
Symptoms
Some devices with an unrecommended BitLocker Group Policy configuration might be required to enter their BitLocker recovery key on the first restart after installing this update.
This issue only affects a limited number of systems in which ALL the following conditions are true. These conditions are unlikely to be found on personal devices not managed by IT departments.
BitLocker is enabled on the OS drive.
The Group Policy Configure TPM platform validation profile for native UEFI firmware configurations is configured, and PCR7 is included in the validation profile (or the equivalent registry key is set manually).
System Information (msinfo32.exe) reports Secure Boot State PCR7 Binding as Not Possible .
The Windows UEFI CA 2023 certificate is present in the device’s Secure Boot Signature Database (DB), making the device eligible for the 2023‑signed Windows Boot Manager to be made the default.
The device is not already running the 2023-signed Windows Boot Manager.
In this scenario, the BitLocker recovery key only needs to be entered once -- subsequent restarts will not trigger a BitLocker recovery screen, as long as the group policy configuration remains unchanged. For help finding your BitLocker recovery key, see [Find your BitLocker recovery ...
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 April 2026
KB5082052
114 CVEs · Critical · exploitedKB5082060
120 CVEs · Critical · exploitedKB5082063
123 CVEs · Critical · exploitedKB5082123
106 CVEs · Critical · exploitedKB5082142
115 CVEs · Critical · exploitedKB5082198
86 CVEs · Critical · exploitedKB5083768
119 CVEs · Critical · exploitedKB5083769
120 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.