---
id: CVE-2026-69304
title: >-
  Improper handling of highly compressed data (data amplification) in ASP.NET
  Core allows an unauthorized attacker to deny service over a network.
summary: >-
  Improper handling of highly compressed data (data amplification) in ASP.NET
  Core allows an unauthorized attacker to deny service over a network.
severity: medium
cvss: 5.9
cvssVector: 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H'
cwe:
  - CWE-409
vendor: Microsoft
product: .NET 10.0
affected:
  - .net_10.0 >= 10.0.0 < 10.0.12
  - .net_8.0 >= 8.0.0 < 8.0.31
  - .net_9.0 >= 9.0.0 < 9.0.20
  - asp.net_core_10.0 >= 10.0 < 10.0.12
  - asp.net_core_11.0 >= 11.0 < 11.0 RC1
  - asp.net_core_8.0 >= 8.0 < 8.0.31
  - asp.net_core_9.0 >= 9.0 < 9.0.20
  - visual_studio_2022_version_17.14 >= 17.14.0 < 17.14.40
  - visual_studio_2026_version_18.9 >= 18.9.0 < 18.9.3
published: '2026-09-08'
updated: '2026-09-08'
sourceUpdated: '2026-09-08T20:17:46.873'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-69304'
references:
  - url: 'https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-69304'
    label: secure@microsoft.com
  - url: >-
      https://github.com/dotnet/aspnetcore/security/advisories/GHSA-8cp2-47hg-mfgh
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-69304'
  - url: 'https://github.com/advisories/GHSA-8cp2-47hg-mfgh'
tags:
  - nvd
  - cve.org
  - ghsa
  - nuget
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-09-08T19:33:58.502592Z'
ingestedAt: '2026-09-08T19:08:49.608Z'
aliases:
  - GHSA-8cp2-47hg-mfgh
ecosystem: nuget
patched:
  - Microsoft.AspNetCore.Server.IISIntegration 11.0.0-rc.1
  - Microsoft.AspNetCore.Server.IISIntegration 8.0.31
  - Microsoft.AspNetCore.Server.IISIntegration 9.0.20
  - Microsoft.AspNetCore.Server.IISIntegration 10.0.12
epss: 0.00768
epssPercentile: 0.54111
---

## Overview

Improper handling of highly compressed data (data amplification) 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-2026-69304)

Affected packages:

- `Microsoft.AspNetCore.Server.IISIntegration >= 11.0.0-preview.1, < 11.0.0-rc.1`
- `Microsoft.AspNetCore.Server.IISIntegration >= 8.0.0, <= 8.0.30`
- `Microsoft.AspNetCore.Server.IISIntegration >= 9.0.0, <= 9.0.19`
- `Microsoft.AspNetCore.Server.IISIntegration >= 10.0.0, <= 10.0.11`

Patched in:

- `Microsoft.AspNetCore.Server.IISIntegration 11.0.0-rc.1`
- `Microsoft.AspNetCore.Server.IISIntegration 8.0.31`
- `Microsoft.AspNetCore.Server.IISIntegration 9.0.20`
- `Microsoft.AspNetCore.Server.IISIntegration 10.0.12`

Source: https://github.com/advisories/GHSA-8cp2-47hg-mfgh