---
id: CVE-2026-45591
title: ASP.NET Core Denial of Service Vulnerability
summary: >-
  Uncontrolled resource consumption in ASP.NET Core allows an unauthorized
  attacker to deny service over a network.
severity: high
cvss: 7.5
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C'
cvssSource: cna
cwe:
  - CWE-400
  - CWE-787
vendor: Microsoft
product: .NET 10.0
affected:
  - .net_10.0 >= 10.0.0 < 10.0.9
  - .net_8.0 >= 8.0.0 < 8.0.28
  - .net_9.0 >= 9.0.0 < 9.0.17
  - asp.net_core_10.0 >= 10.0 < 10.0.9
  - asp.net_core_8.0 >= 8.0 < 8.0.28
  - asp.net_core_9.0 >= 9.0 < 9.0.17
  - visual_studio_2026_version_18.6 >= 18.6.0 < 18.6.3
ssvc:
  exploitation: none
  automatable: 'yes'
  technicalImpact: partial
  timestamp: '2026-06-10T13:47:51.768280Z'
published: '2026-06-09'
updated: '2026-09-24'
sourceUpdated: '2026-09-24T13:44:25.445Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-45591'
references:
  - url: 'https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-45591'
    label: ASP.NET Core Denial of Service Vulnerability
  - url: >-
      https://github.com/dotnet/aspnetcore/security/advisories/GHSA-f8h2-vmm9-qhj6
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-45591'
  - url: 'https://github.com/dotnet/announcements/issues/405'
  - url: 'https://github.com/dotnet/aspnetcore/discussions/67100'
  - url: 'https://github.com/advisories/GHSA-f8h2-vmm9-qhj6'
tags:
  - cve.org
  - ghsa
  - nuget
epss: 0.02444
epssPercentile: 0.83654
aliases:
  - GHSA-f8h2-vmm9-qhj6
ecosystem: nuget
patched:
  - Microsoft.AspNetCore.App.Runtime.linux-x64 8.0.28
  - Microsoft.AspNetCore.App.Runtime.linux-x64 9.0.17
  - Microsoft.AspNetCore.App.Runtime.linux-x64 10.0.9
  - Microsoft.AspNetCore.App.Runtime.win-x64 8.0.28
  - Microsoft.AspNetCore.App.Runtime.win-x64 9.0.17
  - Microsoft.AspNetCore.App.Runtime.win-x64 10.0.9
  - Microsoft.AspNetCore.App.Runtime.osx-arm64 8.0.28
  - Microsoft.AspNetCore.App.Runtime.osx-arm64 9.0.17
  - Microsoft.AspNetCore.App.Runtime.osx-arm64 10.0.9
  - Microsoft.AspNetCore.SignalR.Protocols.MessagePack 8.0.28
  - Microsoft.AspNetCore.SignalR.Protocols.MessagePack 9.0.17
  - Microsoft.AspNetCore.SignalR.Protocols.MessagePack 10.0.9
ingestedAt: '2026-07-07T15:41:58.675Z'
---

## Overview

Uncontrolled resource consumption in ASP.NET Core allows an unauthorized attacker to deny service over a network.

## Affected

- `.net_10.0 >= 10.0.0 < 10.0.9`
- `.net_8.0 >= 8.0.0 < 8.0.28`
- `.net_9.0 >= 9.0.0 < 9.0.17`
- `asp.net_core_10.0 >= 10.0 < 10.0.9`
- `asp.net_core_8.0 >= 8.0 < 8.0.28`
- `asp.net_core_9.0 >= 9.0 < 9.0.17`
- `visual_studio_2026_version_18.6 >= 18.6.0 < 18.6.3`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.

## Package advisory (CVE-2026-45591)

Affected packages:

- `Microsoft.AspNetCore.App.Runtime.linux-x64 >= 8.0.0, <= 8.0.27`
- `Microsoft.AspNetCore.App.Runtime.linux-x64 >= 9.0.0, <= 9.0.16`
- `Microsoft.AspNetCore.App.Runtime.linux-x64 >= 10.0.0, <= 10.0.8`
- `Microsoft.AspNetCore.App.Runtime.win-x64 >= 8.0.0, <= 8.0.27`
- `Microsoft.AspNetCore.App.Runtime.win-x64 >= 9.0.0, <= 9.0.16`
- `Microsoft.AspNetCore.App.Runtime.win-x64 >= 10.0.0, <= 10.0.8`
- `Microsoft.AspNetCore.App.Runtime.osx-arm64 >= 8.0.0, <= 8.0.27`
- `Microsoft.AspNetCore.App.Runtime.osx-arm64 >= 9.0.0, <= 9.0.16`
- `Microsoft.AspNetCore.App.Runtime.osx-arm64 >= 10.0.0, <= 10.0.8`
- `Microsoft.AspNetCore.SignalR.Protocols.MessagePack >= 8.0.0, <= 8.0.27`
- `Microsoft.AspNetCore.SignalR.Protocols.MessagePack >= 9.0.0, <= 9.0.16`
- `Microsoft.AspNetCore.SignalR.Protocols.MessagePack >= 10.0.0, <= 10.0.8`

Patched in:

- `Microsoft.AspNetCore.App.Runtime.linux-x64 8.0.28`
- `Microsoft.AspNetCore.App.Runtime.linux-x64 9.0.17`
- `Microsoft.AspNetCore.App.Runtime.linux-x64 10.0.9`
- `Microsoft.AspNetCore.App.Runtime.win-x64 8.0.28`
- `Microsoft.AspNetCore.App.Runtime.win-x64 9.0.17`
- `Microsoft.AspNetCore.App.Runtime.win-x64 10.0.9`
- `Microsoft.AspNetCore.App.Runtime.osx-arm64 8.0.28`
- `Microsoft.AspNetCore.App.Runtime.osx-arm64 9.0.17`
- `Microsoft.AspNetCore.App.Runtime.osx-arm64 10.0.9`
- `Microsoft.AspNetCore.SignalR.Protocols.MessagePack 8.0.28`
- `Microsoft.AspNetCore.SignalR.Protocols.MessagePack 9.0.17`
- `Microsoft.AspNetCore.SignalR.Protocols.MessagePack 10.0.9`

Source: https://github.com/advisories/GHSA-f8h2-vmm9-qhj6