ASP.NET Core inefficient algorithmic complexity denial of service

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

ASP.NET Core, a web application framework, contains an inefficient algorithm that allows an unauthenticated attacker to crash or severely degrade the performance of web services via the network. The vulnerability can be triggered remotely without authentication, causing denial of service to legitimate users.

Technologies: Microsoft Asp.Net Core, Microsoft.AspNetCore.App.Runtime.linux-arm (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 through 8.0.33; Microsoft.AspNetCore.App.Runtime.linux-arm (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 over the network, in a software library.
Am I affected?
Check whether you run Microsoft Asp.Net Core or Microsoft.AspNetCore.App.Runtime.linux-arm (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

CWE-407 inefficient algorithmic complexity in ASP.NET Core allows unauthenticated remote attackers to trigger worst-case computational complexity and deny service. The vulnerability is exploitable over the network with no privileges or user interaction required. A fix has not been identified in the withdrawn advisory.

Affected products

  • Microsoft ASP.NET Core 8.0.0-preview.1.23112.2 through 8.0.33

Timeline

  • 2026-11-10: disclosed: Advisory published
  • 2026-11-11: withdrawn: Advisory withdrawn as duplicate of GHSA-r3qf-p3jm-8h4p

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