Patch tracker / CVE reference / CVE-2026-21519
CVE-2026-21519
High severity Microsoft vulnerability, CVSS 8.8. Fixed by 12 Microsoft security updates.
All about CVE-2026-21519: the Senserva AI read, whether it is exploited, the official patches, its change history, and the questions admins ask.
CVE-2026-21519 is a high severity Microsoft vulnerability with a CVSS score of 8.8. 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 12 updates below from the Microsoft Update Catalog, and see where this CVE sits against the rest on the patch tracker.
Risk summary
Senserva provides Three Free Unlimited Audits, including all tenants and full Claude MCP.Start my Audit
Senserva AI Opinion for CVE-2026-21519
Desktop Window Manager provides another route to elevated privileges, exploited in the wild and KEV-listed on 2026-02-10 at CVSS 8.8. DWM runs in every interactive Windows session from Windows 10 1809 through Server 2019, making this a broadly useful post-phishing escalation for attackers.
Do this: Sweep for endpoints missing the February 2026 cumulative update and remediate them before month end.
AI-generated from public data, 2026-07-07. Verify against the vendor advisory before acting.
Senserva AI Opinion and rich prompt for CVE-2026-21519
Copy this prompt into Claude, ChatGPT, or Copilot. The facts are included, sourced from this page.
Full tracking and change history for CVE-2026-21519
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 26%. CVSS 8.8 (High).
This CVE is among the lower half of tracked Microsoft CVEs by EPSS exploit probability, and one of 5 actively-exploited CVEs in February 2026.
Official patch(es) for CVE-2026-21519
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 KB5075897, KB5075899, KB5075904, KB5075906, KB5075912, KB5075941, KB5075942, KB5075943, KB5075999, KB5077179, KB5077181, KB5077212 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-2026-21519. 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-2026-21519
Is CVE-2026-21519 actively exploited?
Yes. CVE-2026-21519 is listed in the CISA Known Exploited Vulnerabilities (KEV) catalog, which means exploitation in the wild has been confirmed. Its EPSS exploit probability is 26%.
What patch fixes CVE-2026-21519?
Microsoft fixed CVE-2026-21519 in KB5075897, KB5075899, KB5075904, KB5075906, KB5075912, KB5075941, KB5075942, KB5075943, KB5075999, KB5077179, KB5077181, KB5077212. Download from the Microsoft Update Catalog, or let Intune, Windows Update, or WSUS deliver it.
Which products are affected by CVE-2026-21519?
Windows 10 Version 1809 for 32-bit Systems, Windows 10 Version 1809 for x64-based Systems, Windows Server 2019.
Can I ask my own AI about CVE-2026-21519?
Yes. This page includes a free, ready-to-paste AI prompt containing CVE-2026-21519'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-2026-21519, 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.
