Patch tracker / KB5051987
KB5051987: Windows Server 2025 Security Update (February 2025)
KB5051987 is a High security update for Windows Server 2025, released 2025-02-11. It closes 38 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. The most likely of them to be attacked is CVE-2025-26634, which FIRST.org rates at 40% probability of exploitation in the next 30 days.
Our data comes from Microsoft, CISA and other public sources, and it can be wrong or out of date. If you are unsure, check the linked source before you act, and tell us when we are wrong so we can fix it.
Update summary
Fixes 38 CVEs. At least one is actively exploited (CISA KEV). Most severe CVSS 8.8 (High). EPSS exploit probability up to 40%. Among the top 25% of tracked Microsoft updates by EPSS exploit probability.
A newer security update for Windows Server 2025 (Server Core installation) has shipped since this one: KB5126646 (2026-10-13). 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.
KB5051987 is the broadest March 2025 package in this family at 38 CVEs for Windows 10 1809 and Server 2019, adding CVE-2025-21379, CVE-2025-21182, and CVE-2025-21183 to the common list, while holding the same High, CVSS 8.8 ceiling, 22 percent EPSS, and CISA KEV entry. The extra CVEs suggest this build covers additional optional components not present in the narrower sibling KBs. It is still the same actively exploited vulnerability driving urgency here.
Do this: Deploy KB5051987 wherever the broader optional-component coverage applies, and don't assume a narrower sibling KB is an adequate substitute.
AI-generated from public data, 2026-07-07. Verify against the vendor advisory before acting.
Senserva AI Opinion and rich prompt for KB5051987
Copy this prompt into Claude, ChatGPT, or Copilot. The facts are included, sourced from this page.
Full tracking and change history for KB5051987
- Released
- 2025-03-11
- Last changed
- 2026-09-24
- Changes tracked
- 4
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 KB5051987 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.
Scope and sources
- Affected products
- Also released in February 2025
KB5051974
32 CVEs · High · exploitedKB5051979
34 CVEs · High · exploitedKB5051980
34 CVEs · High · exploitedKB5051989
32 CVEs · High · exploitedKB5052000
34 CVEs · High · exploitedKB5052006
33 CVEs · High · exploitedKB5052016
21 CVEs · High · exploitedKB5052020
23 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.