Patch tracker / KB5094144
KB5094144: Microsoft Exchange Server Subscription Security Update (June 2026)
Updated July 21, 2026. Data refreshed on every build from MSRC, CISA KEV, and FIRST EPSS.
Hot patch: #5 hottest Microsoft update right now, a must-install (as of 2026-07-21)
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Microsoft security update released 2026-06-09. Fixes 8 CVEs.
All about KB5094144: the download, the Senserva AI read, a PowerShell installed-check, install guidance, the CVEs it fixes, and its change history.
KB5094144 is a High security update for Microsoft Exchange Server Subscription, released 2026-06-09. It closes 8 CVEs with a maximum CVSS of 8.8. At least one of them is actively exploited (CISA KEV), so this is a deploy-first update. Get it from the Microsoft Update Catalog below, and see where it sits against the rest of the month on the patch tracker.
Exploitation is not theoretical here: at least one CVE this update fixes is on the CISA Known Exploited Vulnerabilities catalog, which means attackers are already using it against unpatched systems. For an update like this, the risk window is the gap between today and the day your last device installs it, so shortening that gap matters more than perfect scheduling.
Exchange Server updates are their own discipline: they install on the servers themselves (Windows Update, Microsoft Update, or the downloaded package run as administrator), not through Intune device policies. The install guidance below covers the Exchange path. For the bigger picture: how the Microsoft patching tools fit together, this month's Patch Tuesday summary, and every update ranked by real-world risk.
Download KB5094144
Get the official update for KB5094144. The download and file size for each supported product are on the Microsoft Update Catalog page.
Update summary
Senserva AI Opinion for KB5094144
KB5094144 patches 8 CVEs across Exchange Server 2019 (CU14 and CU15) and Exchange Server Subscription Edition, with the worst rated High at CVSS 8.8. One of these CVEs is already listed in the CISA Known Exploited Vulnerabilities catalog, so attackers are actively using at least one of the eight against internet-facing Exchange, even though none are tied to known ransomware campaigns and EPSS tops out at only 6%.
Do this: Schedule this update on your Exchange 2019 and Subscription Edition mailbox servers now, prioritizing any internet-exposed instances given the confirmed CISA KEV listing.
AI-generated from public data, 2026-07-21. Verify against the vendor advisory before acting.
Senserva AI Opinion and rich prompt for KB5094144
Copy this prompt into Claude, ChatGPT, or Copilot. The facts are included, sourced from this page.
Full tracking and change history for KB5094144
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 8 CVEs. At least one is actively exploited (CISA KEV). Most severe CVSS 8.8 (High). EPSS exploit probability up to 5.6%.
Among the top half of tracked Microsoft updates by EPSS exploit probability.
What to do
Treat as urgent: it is being exploited in the wild (CISA KEV), so patch ahead of items that are not. Senserva flags whether KB5094144 is missing on your devices.
Check if KB5094144 is installed
Copy-paste PowerShell: one machine, or your whole fleet 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.
Writing about KB5094144? Cite this page
Copy-paste for a blog post, forum answer, or internal doc. The link always carries the current risk data.
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-2026-42897 | High | 8.8 | 5.6% | KEV |
| CVE-2026-45500 | High | 8.8 | 5.6% | No |
| CVE-2026-45501 | High | 8.8 | 5.6% | No |
| CVE-2026-45502 | High | 8.8 | 5.6% | No |
| CVE-2026-45503 | High | 8.8 | 5.6% | No |
| CVE-2026-45504 | High | 8.8 | 5.6% | No |
| CVE-2026-45583 | High | 8.8 | 5.6% | No |
| CVE-2026-47631 | High | 8.8 | 5.6% | No |
Affected products
Also released in June 2026
The highest-risk updates from the same release:
The full month, summarized: Microsoft Patch Tuesday.
How to install KB5094144
This is an Exchange Server security update. It installs on each Exchange server, not through client update rings:
- Windows Update / Microsoft Update on the server offers Exchange security updates when enabled.
- Manual install: download from the Update Catalog above and run the package from an elevated prompt (running it without elevation is the classic cause of a broken install).
- Verify afterward with Microsoft's Exchange Server Health Checker script, and confirm the build number matches the update.
Common questions about KB5094144
Is KB5094144 urgent?
Yes. KB5094144 fixes at least one vulnerability in the CISA Known Exploited Vulnerabilities catalog, meaning attackers are using it in the wild. Deploy it first.
How do I download KB5094144?
From the Microsoft Update Catalog (linked on this page), or let Intune, Windows Update for Business, Windows Autopatch, or WSUS deliver it. The catalog page lists the download for each supported product.
How do I deploy KB5094144 with Intune?
Assign a Windows Update ring (quality update policy) to the device groups and the update flows on the ring's deferral schedule. Because KB5094144 fixes an actively exploited CVE, an Intune expedite policy is the right tool: it bypasses configured deferrals and pushes the update as soon as devices check in. Verify the rollout with update compliance reporting rather than assuming delivery.
Can I ask my own AI about KB5094144?
Yes. This page includes a free, ready-to-paste AI prompt containing KB5094144's key facts: severity, CVE count, exploitation status, and the download link. Copy it into Claude, ChatGPT, or Copilot for a rollout plan; the data is refreshed three times a day (5 AM, 12:30 PM, and 7 PM US Central).
Authoritative references
See this and every Microsoft update ranked by real-world risk on the Microsoft Patch Tracker.
