Patch tracker / KB5002666

KB5002666: Microsoft SharePoint Server 2019 Security Update (January 2025)

KB5002666 is a High security update for Microsoft SharePoint Server 2019, released 2025-01-14. It closes 3 CVEs with a maximum CVSS of 7.8. It is the 17th largest of the 44 updates Microsoft shipped that month, by CVEs closed.

Update summary

High
2025-01-14
Released
3
CVEs fixed
7.8
Max CVSS v3
High
Severity
Deploy this cycle
Fixes 3 CVEs for Microsoft SharePoint Server 2019. No confirmed in-the-wild exploitation in this set today.

Fixes 3 CVEs. Most severe CVSS 7.8 (High). EPSS exploit probability up to 1.8%. Among the lower half of tracked Microsoft updates by EPSS exploit probability.

Senserva found thiswe track every release for this product line, so we can tell you this package is behind

A newer security update for Microsoft SharePoint Enterprise Server 2016 has shipped since this one: KB5002882 (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.

Microsoft Update Catalog: download KB5002666Microsoft support article
Senserva AI Opinion for KB5002666

SharePoint 2016, 2019, and Subscription Edition administrators need this January update to close CVE-2025-21344, CVE-2025-21348, and CVE-2025-21393, all Severity High at CVSS 7.8. Multiple sibling KBs exist this cycle, so keep an inventory of which farm servers already have one of them installed. None of these three CVEs currently show ransomware association.

Do this: Track patch status across the SharePoint farm to ensure every server gets one of the January update packages.

AI-generated from public data, 2026-07-07. Verify against the vendor advisory before acting.

Senserva AI Opinion and rich prompt for KB5002666

Copy this prompt into Claude, ChatGPT, or Copilot. The facts are included, sourced from this page.

Full tracking and change history for KB5002666

Released
2025-01-14
Last changed
2026-07-29
Changes tracked
3

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 KB5002666 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.

CVESeverityCVSSEPSSExploited
CVE-2025-21344High7.81.8%No
CVE-2025-21348High7.21.8%No
CVE-2025-21393Medium6.31.8%No

Scope and sources

Affected products
Also released in January 2025

KB5049981

121 CVEs · Critical · exploited

KB5049984

128 CVEs · Critical · exploited

KB5050009

128 CVEs · Critical · exploited

KB5050021

121 CVEs · Critical · exploited

KB5049983

122 CVEs · Critical

KB5049993

112 CVEs · Critical

KB5050004

93 CVEs · Critical

KB5050006

71 CVEs · Critical

The full month, summarized: Microsoft Patch Tuesday.

Authoritative references
Official KB5002666 page (Microsoft Support)Microsoft Update CatalogMicrosoft Security Update Guide

See this and every Microsoft update ranked by real-world risk on the Microsoft Patch Tracker.

New to a term on this page? CVE, KB, KEV, CVSS, and EPSS are each explained once, on the Senserva security lexicon. Reference: Microsoft CVE and vulnerability management and the Microsoft patching guide.
Provided as is, without warranty; verify against the vendor advisory before acting. Data notice and terms.