Patch tracker / KB5094128

KB5094128: Windows Server 2019 Security Update (June 2026)

KB5094128 is a Critical security update for Windows Server 2019, released 2026-06-09. It closes 105 CVEs with a maximum CVSS of 9.8. The most likely of them to be attacked is CVE-2026-41108, which FIRST.org rates at 54% probability of exploitation in the next 30 days.

Update summary

Critical
2026-06-09
Released
105
CVEs fixed
9.8
Max CVSS
Critical
Severity
Deploy this cycle
Fixes 105 CVEs for Windows Server 2019. No confirmed in-the-wild exploitation in this set today.

Fixes 105 CVEs. Most severe CVSS 9.8 (Critical). EPSS exploit probability up to 54%. Among the top 25% of tracked Microsoft updates by EPSS exploit probability.

Senserva found thiswe track every release for this product line, so we can tell you this package is behind

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.

Senserva found thisread these before you deploy broadly

Microsoft documents 5 known issues with this update.

  • Devices with an unrecommended BitLocker Group Policy configuration might be required to enter their BitLocker recovery key
  • Windows Server Update Services (WSUS) does not display error details
  • Microsoft Office applications might fail to open from certain third-party apps

The full text, quoted from Microsoft

Microsoft Update Catalog: download KB5094128Microsoft support article
Senserva AI Opinion for KB5094128

KB5094128 is a large June 2026 rollup for Windows 10 Version 1809 and Windows Server 2019, closing 105 CVEs including one rated Critical at CVSS 9.8 with a 54 percent EPSS score, meaning exploitation is plausible in the near term. No CVE here is in the CISA KEV catalog or linked to ransomware yet, but the volume and the high EPSS on the top flaw make this a priority patch. Server 2019 domain controllers and unpatched 1809 endpoints are the most exposed given their typical network exposure.

Do this: Deploy KB5094128 to Windows Server 2019 and Windows 10 1809 systems now, prioritizing internet-facing and domain controller roles.

AI-generated from public data, 2026-07-26. Verify against the vendor advisory before acting.

Senserva AI Opinion and rich prompt for KB5094128

Copy this prompt into Claude, ChatGPT, or Copilot. The facts are included, sourced from this page.

Full tracking and change history for KB5094128

Released
2026-06-09
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 KB5094128 is installed

Elevated PowerShell. No output means it is not installed.

Known issues, from Microsoft

Quoted from Microsoft's support article for KB5094128 (checked 2026-08-04). Verify against the article before acting.

Devices with an unrecommended BitLocker Group Policy configuration might be required to enter their BitLocker recovery key

Symptom

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 of 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 the article, Find your ...

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.

CVESeverityCVSSEPSSExploited
CVE-2026-33828Critical9.854%No
CVE-2026-34335Critical9.854%No
CVE-2026-40404Critical9.854%No
CVE-2026-40409Critical9.854%No
CVE-2026-41092Critical9.854%No
CVE-2026-41108Critical9.854%No
CVE-2026-42828Critical9.854%No
CVE-2026-42836Critical9.854%No
CVE-2026-42837Critical9.854%No
CVE-2026-42903Critical9.854%No
CVE-2026-42904Critical9.854%No
CVE-2026-42905Critical9.854%No
CVE-2026-42906Critical9.854%No
CVE-2026-42907Critical9.854%No
CVE-2026-42908Critical9.854%No
CVE-2026-42909Critical9.854%No
CVE-2026-42911Critical9.854%No
CVE-2026-42912Critical9.854%No
CVE-2026-42913Critical9.854%No
CVE-2026-42914Critical9.854%No
CVE-2026-42915Critical9.854%No
CVE-2026-42916Critical9.854%No
CVE-2026-42968Critical9.854%No
CVE-2026-42969Critical9.854%No
CVE-2026-42970Critical9.854%No
CVE-2026-42971Critical9.854%No
CVE-2026-42972Critical9.854%No
CVE-2026-42973Critical9.854%No
CVE-2026-42974Critical9.854%No
CVE-2026-42977Critical9.854%No
CVE-2026-42978Critical9.854%No
CVE-2026-42979Critical9.854%No
CVE-2026-42980Critical9.854%No
CVE-2026-42981Critical9.854%No
CVE-2026-42983Critical9.854%No
CVE-2026-42984Critical9.854%No
CVE-2026-42985Critical9.854%No
CVE-2026-42986Critical9.854%No
CVE-2026-42987Critical9.854%No
CVE-2026-42989Critical9.854%No
CVE-2026-42991Critical9.854%No
CVE-2026-42992Critical9.854%No
CVE-2026-42993Critical9.854%No
CVE-2026-44799Critical9.854%No
CVE-2026-44801Critical9.854%No
CVE-2026-44802Critical9.854%No
CVE-2026-44803Critical9.854%No
CVE-2026-44805Critical9.854%No
CVE-2026-44810Critical9.854%No
CVE-2026-44812Critical9.854%No
CVE-2026-44815Critical9.854%No
CVE-2026-45487Critical9.854%No
CVE-2026-45586Critical9.854%No
CVE-2026-45588Critical9.854%No
CVE-2026-45592Critical9.854%No
CVE-2026-45593Critical9.854%No
CVE-2026-45594Critical9.854%No
CVE-2026-45595Critical9.854%No
CVE-2026-45596Critical9.854%No
CVE-2026-45597Critical9.854%No
CVE-2026-45598Critical9.854%No
CVE-2026-45599Critical9.854%No
CVE-2026-45601Critical9.854%No
CVE-2026-45602Critical9.854%No
CVE-2026-45603Critical9.854%No
CVE-2026-45605Critical9.854%No
CVE-2026-45606Critical9.854%No
CVE-2026-45607Critical9.854%No
CVE-2026-45608Critical9.854%No
CVE-2026-45634Critical9.854%No
CVE-2026-45635Critical9.854%No
CVE-2026-45636Critical9.854%No
CVE-2026-45637Critical9.854%No
CVE-2026-45638Critical9.854%No
CVE-2026-45639Critical9.854%No
CVE-2026-45640Critical9.854%No
CVE-2026-45641Critical9.854%No
CVE-2026-45642Critical9.854%No
CVE-2026-45648Critical9.854%No
CVE-2026-45653Critical9.854%No
CVE-2026-45655Critical9.854%No
CVE-2026-45656Critical9.854%No
CVE-2026-45657Critical9.854%No
CVE-2026-45658Critical9.854%No
CVE-2026-47288Critical9.854%No
CVE-2026-47289Critical9.854%No
CVE-2026-47291Critical9.854%No
CVE-2026-47648Critical9.854%No
CVE-2026-47652Critical9.854%No
CVE-2026-47653Critical9.854%No
CVE-2026-47654Critical9.854%No
CVE-2026-47656Critical9.854%No
CVE-2026-48563Critical9.854%No
CVE-2026-48568Critical9.854%No
CVE-2026-48570Critical9.854%No
CVE-2026-48573Critical9.854%No
CVE-2026-48574Critical9.854%No
CVE-2026-48575Critical9.854%No
CVE-2026-48576Critical9.854%No
CVE-2026-48578Critical9.854%No
CVE-2026-48583Critical9.854%No
CVE-2026-49160Critical9.854%No
CVE-2026-50507Critical9.854%No
CVE-2026-50508Critical9.854%No
CVE-2026-8863Critical9.854%No

Scope and sources

Affected products
Also released in June 2026

KB5094139

8 CVEs · High · exploited

KB5094140

8 CVEs · High · exploited

KB5094142

8 CVEs · High · exploited

KB5094144

8 CVEs · High · exploited

KB5087423

66 CVEs · Critical

KB5087539

66 CVEs · Critical

KB5089466

61 CVEs · Critical

KB5089549

61 CVEs · Critical

The full month, summarized: Microsoft Patch Tuesday.

Authoritative references
Official KB5094128 page (Microsoft Support)Microsoft Update CatalogMicrosoft Security Update Guide

See this and every Microsoft update ranked by real-world risk on the Microsoft Patch Tracker.

New to a term on this page? CVE, KB, KEV, CVSS, and EPSS are each explained once, on the Senserva security lexicon. Reference: Microsoft CVE and vulnerability management and the Microsoft patching guide.
Provided as is, without warranty; verify against the vendor advisory before acting. Data notice and terms.