Patch tracker / KB5074995
KB5074995: Microsoft Exchange Server Subscription Security Update (February 2026)
KB5074995 is a Medium security update for Microsoft Exchange Server Subscription, released 2026-02-10. It closes 1 CVE with a maximum CVSS of 6.5. The most likely of them to be attacked is CVE-2026-21527, which FIRST.org rates at 8% probability of exploitation in the next 30 days.
Update summary
Fixes 1 CVE. Most severe CVSS 6.5 (Medium). EPSS exploit probability up to 7.7%. Among the top half of tracked Microsoft updates by EPSS exploit probability.
A newer security update for Microsoft Exchange Server Subscription Edition RTM has shipped since this one: KB5121573 (2026-08-11). 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.
KB5074995 patches a single vulnerability (CVE-2026-21527) across Exchange Server Subscription Edition RTM, Exchange 2016 CU23, and Exchange 2019 CU15. It rates Medium (CVSS 6.5) with an 8 percent EPSS and no CISA KEV or ransomware links, so this is a routine on-premises Exchange servicing update rather than an emergency. On-premises Exchange remains a high-value target regardless of any single CVE's rating, which is why keeping the CU baseline current matters here.
Do this: Schedule this update on your on-premises Exchange 2016 CU23, 2019 CU15, and Subscription Edition RTM servers during your next maintenance window.
AI-generated from public data, 2026-07-21. Verify against the vendor advisory before acting.
Senserva AI Opinion and rich prompt for KB5074995
Copy this prompt into Claude, ChatGPT, or Copilot. The facts are included, sourced from this page.
Full tracking and change history for KB5074995
- Released
- 2026-02-10
- Last changed
- 2026-07-13
- 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 KB5074995 is installed
Elevated PowerShell. No output means it is not installed.
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-2026-21527 | Medium | 6.5 | 7.7% | No |
Scope and sources
- Affected products
- Also released in February 2026
KB5075897
29 CVEs · High · exploitedKB5075899
29 CVEs · High · exploitedKB5075904
24 CVEs · High · exploitedKB5075906
27 CVEs · High · exploitedKB5075912
24 CVEs · High · exploitedKB5075941
26 CVEs · High · exploitedKB5075942
29 CVEs · High · exploitedKB5075943
27 CVEs · High · 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.