---
id: CVE-2026-70188
title: >-
  Inconsistent interpretation of http requests ('http request/response
  smuggling') in ASP.NET Core allows an unauthorized attacker to bypass a
  security feature over a network.
summary: >-
  Inconsistent interpretation of http requests ('http request/response
  smuggling') in ASP.NET Core allows an unauthorized attacker to bypass a
  security feature over a network.
severity: critical
cvss: 9.1
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N'
cwe:
  - CWE-444
  - CWE-93
published: '2026-10-13'
updated: '2026-10-14'
sourceUpdated: '2026-10-14T04:18:33.003'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-70188'
references:
  - url: 'https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-70188'
    label: secure@microsoft.com
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-70188.json
  - url: 'https://access.redhat.com/security/cve/CVE-2026-70188'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2548796'
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-70188'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-70188'
  - url: >-
      https://github.com/dotnet/aspnetcore/security/advisories/GHSA-fpq8-4vhr-rcxx
  - url: 'https://github.com/dotnet/announcements/issues/462'
  - url: 'https://github.com/dotnet/aspnetcore/discussions/69798'
  - url: 'https://github.com/advisories/GHSA-fpq8-4vhr-rcxx'
  - url: 'https://access.redhat.com/errata/RHSA-2026:86195'
  - url: 'https://access.redhat.com/errata/RHSA-2026:86168'
  - url: 'https://access.redhat.com/errata/RHSA-2026:86172'
  - url: 'https://access.redhat.com/errata/RHSA-2026:86192'
  - url: 'https://access.redhat.com/errata/RHSA-2026:86594'
  - url: 'https://access.redhat.com/errata/RHSA-2026:86170'
  - url: 'https://access.redhat.com/errata/RHSA-2026:86193'
  - url: 'https://access.redhat.com/errata/RHSA-2026:86169'
  - url: 'https://access.redhat.com/errata/RHSA-2026:86171'
  - url: 'https://access.redhat.com/errata/RHSA-2026:88474'
  - url: 'https://access.redhat.com/errata/RHSA-2026:88424'
  - url: 'https://access.redhat.com/errata/RHSA-2026:88425'
  - url: 'https://access.redhat.com/errata/RHSA-2026:88422'
tags:
  - nvd
  - cve.org
  - csaf
  - vex
  - red-hat
  - ghsa
  - nuget
ingestedAt: '2026-10-13T19:43:29.023Z'
vendor: Microsoft
product: ASP.NET Core 10.0
affected:
  - asp.net_core_10.0 >= 10.0 < 10.0.13
  - asp.net_core_11.0 >= 11.0 < 11.0.0-rc.2
  - asp.net_core_8.0 >= 8.0 < 8.0.32
  - asp.net_core_9.0 >= 9.0 < 9.0.21
  - visual_studio_2022_version_17.14 >= 17.14.0 < 17.14.42
  - visual_studio_2026_version_18.10 >= 18.10.0 < 18.10.4
ssvc:
  exploitation: none
  automatable: 'yes'
  technicalImpact: total
  timestamp: '2026-10-08T00:00:00+00:00'
epss: 0.00938
epssPercentile: 0.60701
aliases:
  - GHSA-fpq8-4vhr-rcxx
ecosystem: nuget
patched:
  - Microsoft.AspNetCore.App.Runtime.linux-arm 11.0.0-rc.2
  - Microsoft.AspNetCore.App.Runtime.linux-arm64 11.0.0-rc.2
  - Microsoft.AspNetCore.App.Runtime.linux-musl-arm 11.0.0-rc.2
  - Microsoft.AspNetCore.App.Runtime.linux-musl-arm64 11.0.0-rc.2
  - Microsoft.AspNetCore.App.Runtime.linux-musl-x64 11.0.0-rc.2
  - Microsoft.AspNetCore.App.Runtime.linux-x64 11.0.0-rc.2
  - Microsoft.AspNetCore.App.Runtime.osx-arm64 11.0.0-rc.2
  - Microsoft.AspNetCore.App.Runtime.osx-x64 11.0.0-rc.2
  - Microsoft.AspNetCore.App.Runtime.win-arm64 11.0.0-rc.2
  - Microsoft.AspNetCore.App.Runtime.win-x64 11.0.0-rc.2
  - Microsoft.AspNetCore.App.Runtime.win-x86 11.0.0-rc.2
  - 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
---

## Overview

Inconsistent interpretation of http requests ('http request/response smuggling') in ASP.NET Core allows an unauthorized attacker to bypass a security feature over a network.

## Remediation

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

## Vendor advisories

- **Red Hat VEX** · Critical · affected: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9 · no fix planned: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9 · updated 2026-10-18 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-70188.json)
- **RHSA-2026:86195** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream (v. 10), Red Hat Enterprise Linux CodeReady Linux Builder (v. 10) · released 2026-10-20 · [advisory](https://access.redhat.com/errata/RHSA-2026:86195)
- **RHSA-2026:86168** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream (v. 10), Red Hat Enterprise Linux CodeReady Linux Builder (v. 10) · released 2026-10-20 · [advisory](https://access.redhat.com/errata/RHSA-2026:86168)
- **RHSA-2026:86172** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream (v. 10), Red Hat Enterprise Linux CodeReady Linux Builder (v. 10) · released 2026-10-20 · [advisory](https://access.redhat.com/errata/RHSA-2026:86172)
- **RHSA-2026:86192** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream (v. 8), Red Hat Enterprise Linux CRB (v. 8) · released 2026-10-20 · [advisory](https://access.redhat.com/errata/RHSA-2026:86192)
- **RHSA-2026:86594** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream (v. 8), Red Hat Enterprise Linux CRB (v. 8) · released 2026-10-21 · [advisory](https://access.redhat.com/errata/RHSA-2026:86594)
- **RHSA-2026:86170** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream (v. 8), Red Hat Enterprise Linux CRB (v. 8) · released 2026-10-20 · [advisory](https://access.redhat.com/errata/RHSA-2026:86170)
- **RHSA-2026:86193** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream (v. 9), Red Hat Enterprise Linux CodeReady Linux Builder (v. 9) · released 2026-10-20 · [advisory](https://access.redhat.com/errata/RHSA-2026:86193)
- **RHSA-2026:86169** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream (v. 9), Red Hat Enterprise Linux CodeReady Linux Builder (v. 9) · released 2026-10-20 · [advisory](https://access.redhat.com/errata/RHSA-2026:86169)
- **RHSA-2026:86171** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream (v. 9), Red Hat Enterprise Linux CodeReady Linux Builder (v. 9) · released 2026-10-20 · [advisory](https://access.redhat.com/errata/RHSA-2026:86171)
- **RHSA-2026:88474** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream EUS (v. 10.0), Red Hat Enterprise Linux CodeReady Linux Builder EUS (v. 10.0) · released 2026-10-22 · [advisory](https://access.redhat.com/errata/RHSA-2026:88474)
- **RHSA-2026:88424** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream EUS (v. 10.0), Red Hat Enterprise Linux CodeReady Linux Builder EUS (v. 10.0) · released 2026-10-22 · [advisory](https://access.redhat.com/errata/RHSA-2026:88424)
- **RHSA-2026:88425** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream E4S (v.9.4) · released 2026-10-22 · [advisory](https://access.redhat.com/errata/RHSA-2026:88425)
- **RHSA-2026:88422** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream EUS (v.9.6), Red Hat CodeReady Linux Builder EUS (v.9.6) · released 2026-10-22 · [advisory](https://access.redhat.com/errata/RHSA-2026:88422)

## Package advisory (CVE-2026-70188)

Affected packages:

- `Microsoft.AspNetCore.App.Runtime.linux-arm >= 11.0.0-preview.1, <= 11.0.0-rc.1`
- `Microsoft.AspNetCore.App.Runtime.linux-arm64 >= 11.0.0-preview.1, <= 11.0.0-rc.1`
- `Microsoft.AspNetCore.App.Runtime.linux-musl-arm >= 11.0.0-preview.1, <= 11.0.0-rc.1`
- `Microsoft.AspNetCore.App.Runtime.linux-musl-arm64 >= 11.0.0-preview.1, <= 11.0.0-rc.1`
- `Microsoft.AspNetCore.App.Runtime.linux-musl-x64 >= 11.0.0-preview.1, <= 11.0.0-rc.1`
- `Microsoft.AspNetCore.App.Runtime.linux-x64 >= 11.0.0-preview.1, <= 11.0.0-rc.1`
- `Microsoft.AspNetCore.App.Runtime.osx-arm64 >= 11.0.0-preview.1, <= 11.0.0-rc.1`
- `Microsoft.AspNetCore.App.Runtime.osx-x64 >= 11.0.0-preview.1, <= 11.0.0-rc.1`
- `Microsoft.AspNetCore.App.Runtime.win-arm64 >= 11.0.0-preview.1, <= 11.0.0-rc.1`
- `Microsoft.AspNetCore.App.Runtime.win-x64 >= 11.0.0-preview.1, <= 11.0.0-rc.1`
- `Microsoft.AspNetCore.App.Runtime.win-x86 >= 11.0.0-preview.1, <= 11.0.0-rc.1`
- `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 11.0.0-rc.2`
- `Microsoft.AspNetCore.App.Runtime.linux-arm64 11.0.0-rc.2`
- `Microsoft.AspNetCore.App.Runtime.linux-musl-arm 11.0.0-rc.2`
- `Microsoft.AspNetCore.App.Runtime.linux-musl-arm64 11.0.0-rc.2`
- `Microsoft.AspNetCore.App.Runtime.linux-musl-x64 11.0.0-rc.2`
- `Microsoft.AspNetCore.App.Runtime.linux-x64 11.0.0-rc.2`
- `Microsoft.AspNetCore.App.Runtime.osx-arm64 11.0.0-rc.2`
- `Microsoft.AspNetCore.App.Runtime.osx-x64 11.0.0-rc.2`
- `Microsoft.AspNetCore.App.Runtime.win-arm64 11.0.0-rc.2`
- `Microsoft.AspNetCore.App.Runtime.win-x64 11.0.0-rc.2`
- `Microsoft.AspNetCore.App.Runtime.win-x86 11.0.0-rc.2`
- `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-fpq8-4vhr-rcxx