Advisory severityMedium6.5Vendor: HighMicrosoft Server

Medium [CVE-2026-50659] .NET Spoofing Vulnerability

This medium-severity Microsoft Server advisory covers CVE-2026-50659 affecting Microsoft .NET Framework 4.8 on Windows Server 2016, Microsoft .NET Framework 4.8 on Windows Server 2012 R2, Microsoft .NET Framework 3.5 AND 4.8 on Windows Server 2019.

Aggregated and source-linked by VulniPulse. Data sources, validation and limitations.

CVE-2026-50659 Source published Jul 14, 2026

VulniPulse record published Jul 16, 2026Record updated Jul 30, 2026

CVE-2026-50659

Affected products & platforms

Microsoft ServerWindows Server

Open source advisory

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Summary

.NET Spoofing Vulnerability

Affected products named by the advisory: Microsoft.NET Framework 4.8 on Windows Server 2016; Microsoft.NET Framework 4.8 on Windows Server 2012; Microsoft.NET Framework 4.8 on Windows Server 2012 R2; Microsoft.NET Framework 3.5 AND 4.8 on Windows Server 2019; and 4 more.

Affected products named by the advisory: Microsoft .NET Framework 3.5 AND 4.8 on Windows Server 2022; Microsoft .NET Framework 3.5 AND 4.7.2 on Windows Server 2019; Microsoft .NET Framework 3.5 AND 4.7.2 on Windows Server 2016; Microsoft .NET Framework 4.6.2/4.7/4.7.1/4.7.2 on Windows Server 2012.

Affected versions

No affected-version range was extracted from the source record. The vendor advisory is authoritative — check it before change work.

Official advisory · high-confidence parse· fetched 2 months ago·verify at source

Fixed versions

KB5104034 (build 10.0.10)
KB5104032 (build 8.0.29)
KB5104033 (build 9.0.18)
KB5101007 (build 4.8.4803.0)
KB5101009 (build 4.8.4803.0)
KB5101011 (build 4.8.4803.0)
KB5101008 (build 2.0.50727.9069 & 3.0.30729.9067 & 4.8.4803.0)
KB5101010 (build 2.0.50727.9182 & 3.0.30729.9168 & 4.8.4803.0)

Official advisory · high-confidence parse· fetched 2 months ago·verify at source

Mitigation checklist

Recommended fix / mitigation

Install the applicable security update for your platform: KB5104034, KB5104032, KB5104033, KB5101007, KB5101009, KB5101011 (see the Microsoft Update Catalog).

Official advisory · high-confidence parse· fetched 2 months ago·verify at source

Sources

Official and corroborating records used to build this advisory.

Microsoft Security Update Guide (MSRC)official
Official vendor source used to discover this advisory; it remains the authority for affected products and remediation. Discovered from the machine-readable feed https://api.msrc.microsoft.com/cvrf/v3.0/updates; this link opens the Microsoft Server advisory index instead of the raw feed document.
Microsoft Server
Official vendor advisoryofficial
Official advisory page fetched and parsed; accepted detail fields are attributed to this page.
Microsoft Server

Cross-references

Validate CVE metadata against the authoritative registries.

CVE-2026-50659NVD CVE.org MITRE

Official resources

Microsoft Update Catalog: KB5104034
Official documentation
Direct download of the KB5104034 security update named in the MSRC remediation data for this CVE.
Microsoft Update Catalog: KB5104032
Official documentation
Direct download of the KB5104032 security update named in the MSRC remediation data for this CVE.
Microsoft Update Catalog: KB5104033
Official documentation
Direct download of the KB5104033 security update named in the MSRC remediation data for this CVE.
MSRC Security Update Guide
Official documentation
Filter by this CVE for per-product KB numbers, severity and exploitability assessment.

Discussion(0)

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