Patch tracker / CVE reference / CVE-2026-20805
CVE-2026-20805
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 10 Microsoft security updates.
All about CVE-2026-20805: the Senserva AI read, whether it is exploited, the official patches, its change history, and the questions admins ask.
CVE-2026-20805 is a critical severity Microsoft vulnerability with a CVSS score of 9.8. It is in the CISA Known Exploited Vulnerabilities catalog: attackers are using it in the wild, which makes it a fix-first item. Microsoft has shipped the fix: deploy one of the 10 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-2026-20805
Despite being labeled an information disclosure flaw in Desktop Window Manager, this carries a Critical severity with a CVSS score of 9.8, which is unusually high for a disclosure bug and suggests the leaked data enables broader compromise. It affects Windows 10 Version 1809 and Windows Server 2019 specifically, and CISA added it to the Known Exploited Vulnerabilities catalog on 2026-01-13 with a 73 percent EPSS score, so active exploitation is confirmed rather than theoretical.
Do this: Deploy Microsoft's patch for CVE-2026-20805 to all Windows 10 1809 and Windows Server 2019 systems now, prioritizing internet-facing and domain controller hosts.
AI-generated from public data, 2026-07-21. Verify against the vendor advisory before acting.
Senserva AI Opinion and rich prompt for CVE-2026-20805
Copy this prompt into Claude, ChatGPT, or Copilot. The facts are included, sourced from this page.
Full tracking and change history for CVE-2026-20805
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
Listed in the CISA Known Exploited Vulnerabilities catalog, confirmed exploited in the wild. EPSS exploit probability 73%. CVSS 9.8 (Critical).
This CVE is among the top 25% of tracked Microsoft CVEs by EPSS exploit probability, and one of 3 actively-exploited CVEs in January 2026.
Official patch(es) for CVE-2026-20805
Treat as urgent: it is being exploited in the wild (CISA KEV), so patch ahead of items that are not. In Intune or Defender, confirm whether the fixing updates KB5073379, KB5073450, KB5073455, KB5073457, KB5073696, KB5073698, KB5073722, KB5073723, KB5073724, KB5074109 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-2026-20805. 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-2026-20805
Is CVE-2026-20805 actively exploited?
Yes. CVE-2026-20805 is listed in the CISA Known Exploited Vulnerabilities (KEV) catalog, which means exploitation in the wild has been confirmed. Its EPSS exploit probability is 73%.
What patch fixes CVE-2026-20805?
Microsoft fixed CVE-2026-20805 in KB5073379, KB5073450, KB5073455, KB5073457, KB5073696, KB5073698, KB5073722, KB5073723, KB5073724, KB5074109. Download from the Microsoft Update Catalog, or let Intune, Windows Update, or WSUS deliver it.
Which products are affected by CVE-2026-20805?
Windows 10 Version 1809 for 32-bit Systems, Windows 10 Version 1809 for x64-based Systems, Windows 11 Version 25H2 for ARM64-based Systems, Windows 11 Version 25H2 for x64-based Systems, Windows Server 2019.
Can I ask my own AI about CVE-2026-20805?
Yes. This page includes a free, ready-to-paste AI prompt containing CVE-2026-20805'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-2026-20805, 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.
