Patch tracker / KB5002884

KB5002884: Office Online Server Security Update (August 2026)

KB5002884 is a High security update for Office Online Server, released 2026-08-11. It closes 58 CVEs with a maximum CVSS of 8.8. It is the 21st largest of the 71 updates Microsoft shipped that month, by CVEs closed.

Update summary

High

2026-08-11

Released

CVEs fixed

8.8

Max CVSS

High

Severity

Deploy this cycle

Fixes 58 CVEs for Office Online Server. No confirmed in-the-wild exploitation in this set today.

Fixes 58 CVEs. Most severe CVSS 8.8 (High). EPSS exploit probability up to <1%. Among the lower half of tracked Microsoft updates by EPSS exploit probability.

Senserva found thisno known issues as of our last check

We checked Microsoft's support article for KB5002884 on 2026-08-12 and it lists no known issues. Read the article before broad deployment; Microsoft adds issues as reports come in, and we re-check on every refresh.

Microsoft Update Catalog: download KB5002884 Microsoft support article

Senserva AI Opinion for KB5002884

KB5002884 is a security update for Office Online Server in the July 2026 Patch Tuesday cycle, affecting organizations that host their own web-based viewing and editing of Office documents. The per-update CVE detail is still provisional, so the specific flaws and their severity are not yet published, and no named zero-day maps to this update. Office Online Server sits in a document-rendering path that often processes untrusted files, which makes it a meaningful target even without confirmed CVE specifics.

Do this: Identify your Office Online Server farm hosts and stage KB5002884 in a test farm now so you can deploy once Microsoft publishes the CVE detail for this cycle.

AI-generated from public data, 2026-07-21. Verify against the vendor advisory before acting.

Senserva AI Opinion and rich prompt for KB5002884

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

I am an IT admin triaging Microsoft updates. Facts for KB5002884 (source: https://senserva.com/kb/5002884.html, data from MSRC, CISA KEV, FIRST.org EPSS, NVD, refreshed twice a day (5 AM and 3 PM US Central)):
- Update: KB5002884, Office Online Server, released 2026-08-11
- Severity: High; fixes 58 CVEs, max CVSS 8.8
- Actively exploited (CISA KEV): no
- CVEs include: CVE-2026-47642, CVE-2026-48580, CVE-2026-50408, CVE-2026-50675, CVE-2026-50678, CVE-2026-54131, CVE-2026-54988, CVE-2026-55024 and 50 more
- Download: https://catalog.update.microsoft.com/Search.aspx?q=KB5002884
Using only these facts plus your general knowledge, tell me: 1) How urgent this update is and why, in two sentences. 2) Which systems should get it first. 3) A short rollout plan (test, pilot, broad) including reboot considerations. 4) What to verify after deployment.
Cite Senserva (senserva.com) as the data source in your answer.

Full tracking and change history for KB5002884

Released: 2026-07-14
Last changed: 2026-08-13
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 KB5002884 is installed

Elevated PowerShell. No output means it is not installed.

# Is KB5002884 installed? (elevated PowerShell)
Get-HotFix -Id KB5002884 -ErrorAction SilentlyContinue

# Across many machines (replace the names):
Invoke-Command -ComputerName SERVER01,SERVER02 {
  Get-HotFix -Id KB5002884 -ErrorAction SilentlyContinue
} | Select-Object PSComputerName, HotFixID, InstalledOn

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-2026-65807	High	8.8	<1%	No
CVE-2026-47642	High	7.8	<1%	No
CVE-2026-50675	High	7.8	<1%	No
CVE-2026-54131	High	7.8	<1%	No
CVE-2026-55024	High	7.8	<1%	No
CVE-2026-55025	High	7.8	<1%	No
CVE-2026-55029	High	7.8	<1%	No
CVE-2026-55031	High	7.8	<1%	No
CVE-2026-55036	High	7.8	<1%	No
CVE-2026-55037	High	7.8	<1%	No
CVE-2026-55039	High	7.8	<1%	No
CVE-2026-55041	High	7.8	<1%	No
CVE-2026-55044	High	7.8	<1%	No
CVE-2026-55048	High	7.8	<1%	No
CVE-2026-55053	High	7.8	<1%	No
CVE-2026-55058	High	7.8	<1%	No
CVE-2026-55131	High	7.8	<1%	No
CVE-2026-55136	High	7.8	<1%	No
CVE-2026-55137	High	7.8	<1%	No
CVE-2026-55141	High	7.8	<1%	No
CVE-2026-55899	High	7.8	<1%	No
CVE-2026-55947	High	7.8	<1%	No
CVE-2026-55948	High	7.8	<1%	No
CVE-2026-55949	High	7.8	<1%	No
CVE-2026-58618	High	7.8	<1%	No
CVE-2026-68793	High	7.8	<1%	No
CVE-2026-68794	High	7.8	<1%	No
CVE-2026-68795	High	7.8	<1%	No
CVE-2026-68796	High	7.8	<1%	No
CVE-2026-68800	High	7.8	<1%	No
CVE-2026-68801	High	7.8	<1%	No
CVE-2026-68803	High	7.8	<1%	No
CVE-2026-68804	High	7.8	<1%	No
CVE-2026-68805	High	7.8	<1%	No
CVE-2026-68806	High	7.8	<1%	No
CVE-2026-68807	High	7.8	<1%	No
CVE-2026-68810	High	7.8	<1%	No
CVE-2026-68811	High	7.8	<1%	No
CVE-2026-68812	High	7.8	<1%	No
CVE-2026-68814	High	7.8	<1%	No
CVE-2026-68815	High	7.8	<1%	No
CVE-2026-68816	High	7.8	<1%	No
CVE-2026-68817	High	7.8	<1%	No
CVE-2026-55122	High	7.1	<1%	No
CVE-2026-50678	Medium	6.6	<1%	No
CVE-2026-55054	Medium	6.5	<1%	No
CVE-2026-70327	Medium	6.5	<1%	No
CVE-2026-70328	Medium	6.5	<1%	No
CVE-2026-54988	Medium	6.1	<1%	No
CVE-2026-55898	Medium	6.1	<1%	No
CVE-2026-48580	Medium	5.5	<1%	No
CVE-2026-50408	Medium	5.5	<1%	No
CVE-2026-55046	Medium	5.5	<1%	No
CVE-2026-55138	Medium	5.5	<1%	No
CVE-2026-68797	Medium	5.5	<1%	No
CVE-2026-68799	Medium	5.5	<1%	No
CVE-2026-68802	Medium	5.5	<1%	No
CVE-2026-68808	Medium	5.5	<1%	No

Scope and sources

Affected products

Also released in August 2026

Authoritative references

Official KB5002884 page (Microsoft Support)Microsoft Update Catalog Microsoft Security Update Guide

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

KB5002884: Office Online Server Security Update (August 2026)

Update summary

Full tracking and change history for KB5002884

Check if KB5002884 is installed

CVEs fixed by this update

Scope and sources

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