Patch tracker / CVE reference / CVE-2026-20943
CVE-2026-20943
Updated July 21, 2026. Data refreshed on every build from MSRC, CISA KEV, and FIRST EPSS.
Critical severity Microsoft vulnerability, CVSS 9.8. Fixed by 4 Microsoft security updates.
All about CVE-2026-20943: the Senserva AI read, whether it is exploited, the official patches, its change history, and the questions admins ask.
CVE-2026-20943 is a critical severity Microsoft vulnerability with a CVSS score of 9.8. Its EPSS score puts the probability of exploitation in the next 30 days at 29%. Microsoft has shipped the fix: deploy one of the 4 updates below from the Microsoft Update Catalog, and see where this CVE sits against the rest on the patch tracker.
Risk summary
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Senserva AI Opinion for CVE-2026-20943
Unlike most of the entries in this batch, which are local privilege escalation bugs, this is a Remote Code Execution flaw in Office's Click-To-Run update mechanism, rated Critical at 9.8 with a 31 percent EPSS score, and it reaches SharePoint Server 2019 as well as Office 2016 in both 32-bit and 64-bit editions. RCE in an update-delivery component is especially serious because it can be triggered without the same local-access prerequisite that most of the other CVEs here require. No confirmed KEV or ransomware use yet.
Do this: Patch SharePoint Server 2019 and any remaining Office 2016 installs first among the Office fixes in this release, given this is remote code execution rather than local escalation.
AI-generated from public data, 2026-07-07. Verify against the vendor advisory before acting.
Senserva AI Opinion and rich prompt for CVE-2026-20943
Copy this prompt into Claude, ChatGPT, or Copilot. The facts are included, sourced from this page.
Full tracking and change history for CVE-2026-20943
Published and last-revised dates are authoritative, from Microsoft MSRC (or the CISA KEV date-added). Senserva additionally records day-to-day changes from 2026-07-07, refreshed several times a day; the change count reflects that forward-only tracking.
Exploitation and severity
Not in the CISA KEV catalog. EPSS exploit probability 29%. CVSS 9.8 (Critical).
This CVE is among the lower half of tracked Microsoft CVEs by EPSS exploit probability.
Official patch(es) for CVE-2026-20943
Elevated priority: high severity or a meaningful exploitation probability, sooner if an affected product is internet-facing. In Intune or Defender, confirm whether the fixing updates KB5002822, KB5002825, KB5002826, KB5002828 are installed across the affected products. Senserva does this automatically across your tenant and flags every missing patch.
Apply the Microsoft security updates below to fix CVE-2026-20943. Each KB page carries the Microsoft Update Catalog download, Microsoft's known issues for the update, a copy-paste PowerShell check for whether it is installed, and the Senserva AI read.
Affected products
Common questions about CVE-2026-20943
Is CVE-2026-20943 actively exploited?
It is not currently listed in the CISA Known Exploited Vulnerabilities catalog. Its EPSS score puts the probability of exploitation in the next 30 days at 29%.
What patch fixes CVE-2026-20943?
Microsoft fixed CVE-2026-20943 in KB5002822, KB5002825, KB5002826, KB5002828. Download from the Microsoft Update Catalog, or let Intune, Windows Update, or WSUS deliver it.
Which products are affected by CVE-2026-20943?
Microsoft Office 2016 (32-bit edition), Microsoft Office 2016 (64-bit edition), Microsoft SharePoint Server 2019.
Can I ask my own AI about CVE-2026-20943?
Yes. This page includes a free, ready-to-paste AI prompt containing CVE-2026-20943's key facts: severity, CVSS, EPSS exploit probability, CISA KEV status, and the fixing KB. Copy it into Claude, ChatGPT, or Copilot for a triage plan; the data is refreshed three times a day (5 AM, 12:30 PM, and 7 PM US Central).
Fixed by the same updates
If you are patching CVE-2026-20943, the same updates also fix these:
Authoritative references
Want every Microsoft CVE and the patches that fix it, ranked by real-world risk? See the Microsoft Patch Tracker.
