Microsoft ASP.NET Core race condition privilege escalation

Severity: high · CVSS 7.5 · Published 2026-11-10

ASP.NET Core, Microsoft's web application framework, contains a race condition that allows an authorized attacker to escalate privileges locally. An attacker with limited access could exploit timing windows in shared resource access to gain elevated permissions on the system running the application.

Technologies: Microsoft Asp.Net Core, Microsoft.AspNetCore.App.Runtime.win-arm64 (NuGet). Vendors: Microsoft, NuGet.

Quick answers

Is This vulnerability exploited in the wild?
No. Junglewise Threat Intelligence has no report of This vulnerability being exploited in the wild.
How severe is This vulnerability?
High severity, with a CVSS score of 7.5, published 10 November 2026.
Which products and versions are affected?
Microsoft Asp.Net Core >= 8.0.0-preview.1.23112.2, <= 8.0.33; Microsoft.AspNetCore.App.Runtime.win-arm64 (NuGet) >= 8.0.0-preview.1.23112.2, <= 8.0.33, ECOSYSTEM:introduced=8.0.0-preview.1.23112.2,last_affected=8.0.33.
Is there a fix for This vulnerability?
No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
How is This vulnerability attacked?
It is attacked with local access, in a software library.
Am I affected?
Check whether you run Microsoft Asp.Net Core or Microsoft.AspNetCore.App.Runtime.win-arm64 (NuGet) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

A race condition (CWE-362) in ASP.NET Core allows concurrent execution with improper synchronization of shared resources. An authenticated local attacker with low privileges can exploit a timing window to escalate to higher privileges. The vulnerability requires local access and specific conditions to trigger, but results in privilege elevation.

Affected products

  • Microsoft ASP.NET Core >= 8.0.0-preview.1.23112.2, <= 8.0.33

Timeline

  • 2026-11-10: disclosed

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