Patch tracker / KB5063223
KB5063223: Microsoft Exchange Server 2019 Cumulat Security Update (August 2025)
KB5063223 is a High security update for Microsoft Exchange Server 2019 Cumulat, released 2025-08-12. It closes 4 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 KB5063223
KB5063223 patches four CVEs across on-premises Exchange Server 2016 CU23 and 2019 CU14 and CU15, with the worst rated High severity at CVSS 7.5. None are on the CISA KEV list or tied to ransomware, and EPSS peaks at only 1 percent, so this is maintenance for internet-facing mail infrastructure rather than an emergency. The exposure is any organization still running on-premises Exchange, which remains a favored target regardless of current exploitation data.
Do this: Schedule this cumulative update across your Exchange 2016 CU23 and 2019 CU14 or CU15 servers, applying it to internet-facing roles first.
AI-generated from public data, 2026-07-21. Verify against the vendor advisory before acting.
Senserva AI Opinion and rich prompt for KB5063223
Copy this prompt into Claude, ChatGPT, or Copilot. The facts are included, sourced from this page.
Full tracking and change history for KB5063223
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 4 CVEs. Most severe CVSS 7.5 (High). EPSS exploit probability up to 1.3%.
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 KB5063223 is missing on your devices.
Check if KB5063223 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-2025-25005 | High | 7.5 | 1.3% | No |
| CVE-2025-25006 | High | 7.5 | 1.3% | No |
| CVE-2025-25007 | High | 7.5 | 1.3% | No |
| CVE-2025-33051 | High | 7.5 | 1.3% | No |
Affected products
Also released in August 2025
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.