---
id: CVE-2026-70186
title: >-
  Deadlock in ASP.NET Core allows an unauthorized attacker to deny service over
  a network.
summary: >-
  Deadlock 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'
cwe:
  - CWE-833
vendor: Microsoft
product: Microsoft.AspNetCore.App.Runtime.linux-arm
affected:
  - 'Microsoft.AspNetCore.App.Runtime.linux-arm >= 8.0.0, <= 8.0.31'
  - 'Microsoft.AspNetCore.App.Runtime.linux-arm64 >= 8.0.0, <= 8.0.31'
  - 'Microsoft.AspNetCore.App.Runtime.linux-musl-arm >= 8.0.0, <= 8.0.31'
  - 'Microsoft.AspNetCore.App.Runtime.linux-musl-arm64 >= 8.0.0, <= 8.0.31'
  - 'Microsoft.AspNetCore.App.Runtime.linux-musl-x64 >= 8.0.0, <= 8.0.31'
  - 'Microsoft.AspNetCore.App.Runtime.linux-x64 >= 8.0.0, <= 8.0.31'
  - 'Microsoft.AspNetCore.App.Runtime.osx-arm64 >= 8.0.0, <= 8.0.31'
  - 'Microsoft.AspNetCore.App.Runtime.osx-x64 >= 8.0.0, <= 8.0.31'
  - 'Microsoft.AspNetCore.App.Runtime.win-arm64 >= 8.0.0, <= 8.0.31'
  - 'Microsoft.AspNetCore.App.Runtime.win-x64 >= 8.0.0, <= 8.0.31'
  - 'Microsoft.AspNetCore.App.Runtime.win-x86 >= 8.0.0, <= 8.0.31'
  - 'Microsoft.AspNetCore.App.Runtime.linux-arm >= 10.0.0, <= 10.0.12'
  - 'Microsoft.AspNetCore.App.Runtime.linux-arm64 >= 10.0.0, <= 10.0.12'
  - 'Microsoft.AspNetCore.App.Runtime.linux-musl-arm >= 10.0.0, <= 10.0.12'
  - 'Microsoft.AspNetCore.App.Runtime.linux-musl-arm64 >= 10.0.0, <= 10.0.12'
  - 'Microsoft.AspNetCore.App.Runtime.linux-musl-x64 >= 10.0.0, <= 10.0.12'
  - 'Microsoft.AspNetCore.App.Runtime.linux-x64 >= 10.0.0, <= 10.0.12'
  - 'Microsoft.AspNetCore.App.Runtime.osx-arm64 >= 10.0.0, <= 10.0.12'
  - 'Microsoft.AspNetCore.App.Runtime.osx-x64 >= 10.0.0, <= 10.0.12'
  - 'Microsoft.AspNetCore.App.Runtime.win-arm64 >= 10.0.0, <= 10.0.12'
  - 'Microsoft.AspNetCore.App.Runtime.win-x64 >= 10.0.0, <= 10.0.12'
  - 'Microsoft.AspNetCore.App.Runtime.win-x86 >= 10.0.0, <= 10.0.12'
  - 'Microsoft.AspNetCore.App.Runtime.linux-arm >= 9.0.0, <= 9.0.20'
  - 'Microsoft.AspNetCore.App.Runtime.linux-arm64 >= 9.0.0, <= 9.0.20'
  - 'Microsoft.AspNetCore.App.Runtime.linux-musl-arm >= 9.0.0, <= 9.0.20'
  - 'Microsoft.AspNetCore.App.Runtime.linux-musl-arm64 >= 9.0.0, <= 9.0.20'
  - 'Microsoft.AspNetCore.App.Runtime.linux-musl-x64 >= 9.0.0, <= 9.0.20'
  - 'Microsoft.AspNetCore.App.Runtime.linux-x64 >= 9.0.0, <= 9.0.20'
  - 'Microsoft.AspNetCore.App.Runtime.osx-arm64 >= 9.0.0, <= 9.0.20'
  - 'Microsoft.AspNetCore.App.Runtime.osx-x64 >= 9.0.0, <= 9.0.20'
  - 'Microsoft.AspNetCore.App.Runtime.win-arm64 >= 9.0.0, <= 9.0.20'
  - 'Microsoft.AspNetCore.App.Runtime.win-x64 >= 9.0.0, <= 9.0.20'
  - 'Microsoft.AspNetCore.App.Runtime.win-x86 >= 9.0.0, <= 9.0.20'
patched:
  - Microsoft.AspNetCore.App.Runtime.linux-arm 8.0.32
  - Microsoft.AspNetCore.App.Runtime.linux-arm64 8.0.32
  - Microsoft.AspNetCore.App.Runtime.linux-musl-arm 8.0.32
  - Microsoft.AspNetCore.App.Runtime.linux-musl-arm64 8.0.32
  - Microsoft.AspNetCore.App.Runtime.linux-musl-x64 8.0.32
  - Microsoft.AspNetCore.App.Runtime.linux-x64 8.0.32
  - Microsoft.AspNetCore.App.Runtime.osx-arm64 8.0.32
  - Microsoft.AspNetCore.App.Runtime.osx-x64 8.0.32
  - Microsoft.AspNetCore.App.Runtime.win-arm64 8.0.32
  - Microsoft.AspNetCore.App.Runtime.win-x64 8.0.32
  - Microsoft.AspNetCore.App.Runtime.win-x86 8.0.32
  - Microsoft.AspNetCore.App.Runtime.linux-arm 10.0.13
  - Microsoft.AspNetCore.App.Runtime.linux-arm64 10.0.13
  - Microsoft.AspNetCore.App.Runtime.linux-musl-arm 10.0.13
  - Microsoft.AspNetCore.App.Runtime.linux-musl-arm64 10.0.13
  - Microsoft.AspNetCore.App.Runtime.linux-musl-x64 10.0.13
  - Microsoft.AspNetCore.App.Runtime.linux-x64 10.0.13
  - Microsoft.AspNetCore.App.Runtime.osx-arm64 10.0.13
  - Microsoft.AspNetCore.App.Runtime.osx-x64 10.0.13
  - Microsoft.AspNetCore.App.Runtime.win-arm64 10.0.13
  - Microsoft.AspNetCore.App.Runtime.win-x64 10.0.13
  - Microsoft.AspNetCore.App.Runtime.win-x86 10.0.13
  - Microsoft.AspNetCore.App.Runtime.linux-arm 9.0.21
  - Microsoft.AspNetCore.App.Runtime.linux-arm64 9.0.21
  - Microsoft.AspNetCore.App.Runtime.linux-musl-arm 9.0.21
  - Microsoft.AspNetCore.App.Runtime.linux-musl-arm64 9.0.21
  - Microsoft.AspNetCore.App.Runtime.linux-musl-x64 9.0.21
  - Microsoft.AspNetCore.App.Runtime.linux-x64 9.0.21
  - Microsoft.AspNetCore.App.Runtime.osx-arm64 9.0.21
  - Microsoft.AspNetCore.App.Runtime.osx-x64 9.0.21
  - Microsoft.AspNetCore.App.Runtime.win-arm64 9.0.21
  - Microsoft.AspNetCore.App.Runtime.win-x64 9.0.21
  - Microsoft.AspNetCore.App.Runtime.win-x86 9.0.21
published: '2026-10-13'
updated: '2026-10-13'
sourceUpdated: '2026-10-13T23:17:59.340'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-70186'
references:
  - url: 'https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-70186'
    label: secure@microsoft.com
  - url: >-
      https://github.com/dotnet/aspnetcore/security/advisories/GHSA-mf4x-w4gh-4656
  - url: 'https://github.com/dotnet/announcements/issues/461'
  - url: 'https://github.com/dotnet/aspnetcore/discussions/69797'
  - url: 'https://github.com/advisories/GHSA-mf4x-w4gh-4656'
tags:
  - nvd
  - ghsa
  - nuget
aliases:
  - GHSA-mf4x-w4gh-4656
ecosystem: nuget
ingestedAt: '2026-10-13T19:43:29.022Z'
---

## Overview

Deadlock in ASP.NET Core allows an unauthorized attacker to deny service over a network.

## Remediation

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

## Package advisory (CVE-2026-70186)

Affected packages:

- `Microsoft.AspNetCore.App.Runtime.linux-arm >= 8.0.0, <= 8.0.31`
- `Microsoft.AspNetCore.App.Runtime.linux-arm64 >= 8.0.0, <= 8.0.31`
- `Microsoft.AspNetCore.App.Runtime.linux-musl-arm >= 8.0.0, <= 8.0.31`
- `Microsoft.AspNetCore.App.Runtime.linux-musl-arm64 >= 8.0.0, <= 8.0.31`
- `Microsoft.AspNetCore.App.Runtime.linux-musl-x64 >= 8.0.0, <= 8.0.31`
- `Microsoft.AspNetCore.App.Runtime.linux-x64 >= 8.0.0, <= 8.0.31`
- `Microsoft.AspNetCore.App.Runtime.osx-arm64 >= 8.0.0, <= 8.0.31`
- `Microsoft.AspNetCore.App.Runtime.osx-x64 >= 8.0.0, <= 8.0.31`
- `Microsoft.AspNetCore.App.Runtime.win-arm64 >= 8.0.0, <= 8.0.31`
- `Microsoft.AspNetCore.App.Runtime.win-x64 >= 8.0.0, <= 8.0.31`
- `Microsoft.AspNetCore.App.Runtime.win-x86 >= 8.0.0, <= 8.0.31`
- `Microsoft.AspNetCore.App.Runtime.linux-arm >= 10.0.0, <= 10.0.12`
- `Microsoft.AspNetCore.App.Runtime.linux-arm64 >= 10.0.0, <= 10.0.12`
- `Microsoft.AspNetCore.App.Runtime.linux-musl-arm >= 10.0.0, <= 10.0.12`
- `Microsoft.AspNetCore.App.Runtime.linux-musl-arm64 >= 10.0.0, <= 10.0.12`
- `Microsoft.AspNetCore.App.Runtime.linux-musl-x64 >= 10.0.0, <= 10.0.12`
- `Microsoft.AspNetCore.App.Runtime.linux-x64 >= 10.0.0, <= 10.0.12`
- `Microsoft.AspNetCore.App.Runtime.osx-arm64 >= 10.0.0, <= 10.0.12`
- `Microsoft.AspNetCore.App.Runtime.osx-x64 >= 10.0.0, <= 10.0.12`
- `Microsoft.AspNetCore.App.Runtime.win-arm64 >= 10.0.0, <= 10.0.12`
- `Microsoft.AspNetCore.App.Runtime.win-x64 >= 10.0.0, <= 10.0.12`
- `Microsoft.AspNetCore.App.Runtime.win-x86 >= 10.0.0, <= 10.0.12`
- `Microsoft.AspNetCore.App.Runtime.linux-arm >= 9.0.0, <= 9.0.20`
- `Microsoft.AspNetCore.App.Runtime.linux-arm64 >= 9.0.0, <= 9.0.20`
- `Microsoft.AspNetCore.App.Runtime.linux-musl-arm >= 9.0.0, <= 9.0.20`
- `Microsoft.AspNetCore.App.Runtime.linux-musl-arm64 >= 9.0.0, <= 9.0.20`
- `Microsoft.AspNetCore.App.Runtime.linux-musl-x64 >= 9.0.0, <= 9.0.20`
- `Microsoft.AspNetCore.App.Runtime.linux-x64 >= 9.0.0, <= 9.0.20`
- `Microsoft.AspNetCore.App.Runtime.osx-arm64 >= 9.0.0, <= 9.0.20`
- `Microsoft.AspNetCore.App.Runtime.osx-x64 >= 9.0.0, <= 9.0.20`
- `Microsoft.AspNetCore.App.Runtime.win-arm64 >= 9.0.0, <= 9.0.20`
- `Microsoft.AspNetCore.App.Runtime.win-x64 >= 9.0.0, <= 9.0.20`
- `Microsoft.AspNetCore.App.Runtime.win-x86 >= 9.0.0, <= 9.0.20`

Patched in:

- `Microsoft.AspNetCore.App.Runtime.linux-arm 8.0.32`
- `Microsoft.AspNetCore.App.Runtime.linux-arm64 8.0.32`
- `Microsoft.AspNetCore.App.Runtime.linux-musl-arm 8.0.32`
- `Microsoft.AspNetCore.App.Runtime.linux-musl-arm64 8.0.32`
- `Microsoft.AspNetCore.App.Runtime.linux-musl-x64 8.0.32`
- `Microsoft.AspNetCore.App.Runtime.linux-x64 8.0.32`
- `Microsoft.AspNetCore.App.Runtime.osx-arm64 8.0.32`
- `Microsoft.AspNetCore.App.Runtime.osx-x64 8.0.32`
- `Microsoft.AspNetCore.App.Runtime.win-arm64 8.0.32`
- `Microsoft.AspNetCore.App.Runtime.win-x64 8.0.32`
- `Microsoft.AspNetCore.App.Runtime.win-x86 8.0.32`
- `Microsoft.AspNetCore.App.Runtime.linux-arm 10.0.13`
- `Microsoft.AspNetCore.App.Runtime.linux-arm64 10.0.13`
- `Microsoft.AspNetCore.App.Runtime.linux-musl-arm 10.0.13`
- `Microsoft.AspNetCore.App.Runtime.linux-musl-arm64 10.0.13`
- `Microsoft.AspNetCore.App.Runtime.linux-musl-x64 10.0.13`
- `Microsoft.AspNetCore.App.Runtime.linux-x64 10.0.13`
- `Microsoft.AspNetCore.App.Runtime.osx-arm64 10.0.13`
- `Microsoft.AspNetCore.App.Runtime.osx-x64 10.0.13`
- `Microsoft.AspNetCore.App.Runtime.win-arm64 10.0.13`
- `Microsoft.AspNetCore.App.Runtime.win-x64 10.0.13`
- `Microsoft.AspNetCore.App.Runtime.win-x86 10.0.13`
- `Microsoft.AspNetCore.App.Runtime.linux-arm 9.0.21`
- `Microsoft.AspNetCore.App.Runtime.linux-arm64 9.0.21`
- `Microsoft.AspNetCore.App.Runtime.linux-musl-arm 9.0.21`
- `Microsoft.AspNetCore.App.Runtime.linux-musl-arm64 9.0.21`
- `Microsoft.AspNetCore.App.Runtime.linux-musl-x64 9.0.21`
- `Microsoft.AspNetCore.App.Runtime.linux-x64 9.0.21`
- `Microsoft.AspNetCore.App.Runtime.osx-arm64 9.0.21`
- `Microsoft.AspNetCore.App.Runtime.osx-x64 9.0.21`
- `Microsoft.AspNetCore.App.Runtime.win-arm64 9.0.21`
- `Microsoft.AspNetCore.App.Runtime.win-x64 9.0.21`
- `Microsoft.AspNetCore.App.Runtime.win-x86 9.0.21`

Source: https://github.com/advisories/GHSA-mf4x-w4gh-4656