CERT-FR flags multiple Microsoft .NET flaws
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CERT-FR advisory lists numerous vulnerabilities in Microsoft .NET, ASP.NET Core and .NET Framework enabling RCE, privilege escalation and denial of service; patches required.
CERT-FR has published an advisory consolidating multiple vulnerabilities affecting Microsoft .NET versions 8.0, 9.0, 10.0 and 11.0 (RC), ASP.NET Core 8.0-11.0, and Microsoft .NET Framework versions 3.5 through 4.8.1, across Windows, Linux and macOS platforms. The bulletin references over 40 distinct CVEs disclosed by Microsoft on 13 October 2026, covering risks including remote code execution, privilege escalation, denial of service, data confidentiality and integrity breaches, and security bypass.
No exploitation in the wild is mentioned in the advisory. CERT-FR directs administrators to consult Microsoft's security bulletins for each CVE and apply the corresponding patches. Given the broad scope of affected .NET and .NET Framework versions used widely in enterprise application development and web services (ASP.NET Core), organizations should prioritize patching based on exposure, particularly for internet-facing ASP.NET Core deployments where RCE vulnerabilities pose the greatest risk.
This is a routine, no-evidence-of-exploitation patch advisory from a national CERT compiling a Microsoft Patch Tuesday-style release; severity is assessed as medium absent confirmation of active exploitation, though the presence of multiple RCE and privilege escalation CVEs warrants timely remediation.
Mentioned in this report
Source reporting: https://www.cert.ssi.gouv.fr/avis/CERTFR-2026-AVI-1313
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