Patch tracker / CVE reference / CVE-2026-50646

CVE-2026-50646

CVE-2026-50646 is a critical severity Microsoft vulnerability with a CVSS score of 9.9. Microsoft has shipped the fix: deploy one of the 21 updates below from the Microsoft Update Catalog, and see where this CVE sits against the rest on the patch tracker.

Critical

Critical severity Microsoft vulnerability, CVSS 9.9. Fixed by 21 Microsoft security updates.

Senserva AI read on CVE-2026-50646Official patches for CVE-2026-50646Change historyAdmin questions

Risk summary

CVSS base
9.9
EPSS exploit probability
7.5%
Severity
Critical
Schedule normally
No exploitation observed: not in the CISA KEV catalog, EPSS 7%.
Fixed by KB5099535 and 20 more (by build, listed below). Download from the Microsoft Update Catalog, or deploy via Windows Update, Intune, or WSUS.
Do this now: Deploy with your normal update cycle. This page refreshes daily; the verdict changes the day the data does.

Updated July 23, 2026. Data refreshed on every build from MSRC, CISA KEV, and FIRST EPSS.

Senserva AI Opinion for CVE-2026-50646

CVE-2026-50646 is a remote code execution flaw in .NET Framework 4.8 (and 3.5 on Windows 10 1809), rated High severity at CVSS 7.8. Exposure spans Windows Server 2012, Server 2016 Server Core, and Windows 10 1809 x64 systems running these framework versions, including older Server Core boxes that often run unattended. The 7.8 score with a local attack profile means an attacker who already has a foothold or can get code to run under a user context can escalate to full execution, so it matters most on shared or multi-user hosts.

Do this: Deploy the Microsoft .NET Framework security update to your Server 2012, Server 2016 Server Core, and Windows 10 1809 systems, confirming both the 3.5 and 4.8 update packages install on the 1809 hosts.

AI-generated from public data, 2026-07-22. Verify against the vendor advisory before acting.

Senserva AI Opinion and rich prompt for CVE-2026-50646

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

Full tracking and change history for CVE-2026-50646

Published
2026-07-14
Last revised
2026-07-20
Changes tracked
2

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 7.5%. CVSS 9.9 (Critical).

This CVE is among the lower half of tracked Microsoft CVEs by EPSS exploit probability.

Official patch(es) for CVE-2026-50646

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 KB5099535, KB5100984, KB5100985, KB5100989, KB5100990, KB5100991, KB5100998, KB5101000, KB5101001, KB5101002, KB5101004, KB5101005, KB5101006, KB5101007, KB5101008, KB5101009, KB5101010, KB5101011, KB5101014, KB5104032, KB5104033 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-2026-50646. 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.

KB5099535KB5100984KB5100985KB5100989KB5100990KB5100991KB5100998KB5101000KB5101001KB5101002KB5101004KB5101005KB5101006KB5101007KB5101008KB5101009KB5101010KB5101011KB5101014KB5104032KB5104033

Affected products

Common questions about CVE-2026-50646

Is CVE-2026-50646 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 7.5%.

What patch fixes CVE-2026-50646?

Microsoft fixed CVE-2026-50646 in KB5099535, KB5100984, KB5100985, KB5100989, KB5100990, KB5100991, KB5100998, KB5101000, KB5101001, KB5101002, KB5101004, KB5101005, KB5101006, KB5101007, KB5101008, KB5101009, KB5101010, KB5101011, KB5101014, KB5104032, KB5104033. Download from the Microsoft Update Catalog, or let Intune, Windows Update, or WSUS deliver it.

Which products are affected by CVE-2026-50646?

.NET 10.0 installed on Linux, .NET 10.0 installed on Mac OS, .NET 10.0 installed on Windows, .NET 8.0 installed on Mac OS, .NET 8.0 installed on Windows, 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-2026-50646?

Yes. This page includes a free, ready-to-paste AI prompt containing CVE-2026-50646'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-2026-50646, the same updates also fix these:

CVE-2026-56155CVE-2026-33842CVE-2026-34346CVE-2026-40378CVE-2026-40400CVE-2026-40422CVE-2026-41087CVE-2026-42900

Authoritative references

Official CVE record (cve.org)NVD detailMicrosoft MSRCFIRST.org EPSS

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Lexicon: the terms on this page
CVE
Common Vulnerabilities and Exposures. A unique ID for one publicly known vulnerability, such as CVE-2025-1234.
KB
Microsoft Knowledge Base article. The identifier for a specific Microsoft update.
KEV
CISA Known Exploited Vulnerabilities. CVEs confirmed exploited in the wild. Fix these first.
CVSS
Common Vulnerability Scoring System. A standardized Severity score from 0 to 10.
EPSS
Exploit Prediction Scoring System. The probability a CVE will be exploited in the next 30 days.
MSRC
Microsoft Security Response Center. Microsoft's Patch Tuesday advisories and KB-to-CVE mapping.
NVD
National Vulnerability Database (NIST). Authoritative CVE metadata and CVSS scores.
Ransomware
The vulnerability is linked to known ransomware activity.
Reference: Microsoft CVE and vulnerability management, the full CVE-to-patch lookup ranked by real-world risk, and the Microsoft patching guide, how Intune, Windows Autopatch, Defender, and Azure Update Manager fit together.
Data notice: this page, the feeds, and the API are provided as is, for informational purposes only, without warranty of any kind. Senserva, LLC does not guarantee the accuracy, completeness, or timeliness of third-party data (MSRC, NVD, CISA KEV, EPSS) and accepts no liability for actions taken based on it; verify against the authoritative vendor advisory before acting. Built daily with Senserva Trustworthy AI. All use of this data is subject to the Senserva EULA.