Patch tracker / KB5094144
KB5094144: Microsoft Exchange Server 2016 Cumulat Security Update (June 2026)
KB5094144 is a High security update for Microsoft Exchange Server 2016 Cumulat, 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.
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 KB5094144
KB5094144 patches 8 CVEs across Exchange Server 2019 CU14, CU15, and Subscription Edition RTM, with a highest Severity of High (CVSS 8.8). One of these CVEs is already listed in the CISA Known Exploited Vulnerabilities catalog, which means attackers are using it in the wild against on-premises Exchange, though none is currently tied to ransomware campaigns.
Do this: Schedule and apply KB5094144 to all Exchange 2019 CU14, CU15, and Subscription Edition RTM servers now, prioritizing internet-facing mailbox roles given the confirmed KEV exploitation.
AI-generated from public data, 2026-07-25. 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 70%.
Among the top 25% 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 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.
Known issues
Microsoft's support article for KB5094144 lists no known issues as of 2026-08-04. Check the article before broad deployment; Microsoft updates it as reports come in.
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 | 70% | KEV |
| CVE-2026-45500 | Critical | 9.6 | 70% | No |
| CVE-2026-45501 | Critical | 9.6 | 70% | No |
| CVE-2026-45502 | Critical | 9.6 | 70% | No |
| CVE-2026-45503 | Critical | 9.6 | 70% | No |
| CVE-2026-45504 | Critical | 9.6 | 70% | No |
| CVE-2026-45583 | Critical | 9.6 | 70% | No |
| CVE-2026-47631 | Critical | 9.6 | 70% | No |
Affected products
Also released in June 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.