Microsoft Security Advisory CVE-2026-88092 - ASP.NET Core Security Feature Bypass Vulnerability

[ Why it matters ]Priority signals

• Critical severity: CVSS 9.4

[ Description ]Official description

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

[ Fixes ]Fixes and patches

• Microsoft.AspNetCore.App.Runtime.linux-arm 8.0.32Fixed version · GitHub Advisories · nuget package Microsoft.AspNetCore.App.Runtime.linux-arm: upgrade to 8.0.32 or later (affected >= 8.0.0, <= 8.0.31)
• Microsoft.AspNetCore.App.Runtime.linux-arm64 8.0.32Fixed version · GitHub Advisories · nuget package Microsoft.AspNetCore.App.Runtime.linux-arm64: upgrade to 8.0.32 or later (affected >= 8.0.0, <= 8.0.31)
• Microsoft.AspNetCore.App.Runtime.linux-musl-arm 8.0.32Fixed version · GitHub Advisories · nuget package Microsoft.AspNetCore.App.Runtime.linux-musl-arm: upgrade to 8.0.32 or later (affected >= 8.0.0, <= 8.0.31)
• Microsoft.AspNetCore.App.Runtime.linux-musl-arm64 8.0.32Fixed version · GitHub Advisories · nuget package Microsoft.AspNetCore.App.Runtime.linux-musl-arm64: upgrade to 8.0.32 or later (affected >= 8.0.0, <= 8.0.31)
• Microsoft.AspNetCore.App.Runtime.linux-musl-x64 8.0.32Fixed version · GitHub Advisories · nuget package Microsoft.AspNetCore.App.Runtime.linux-musl-x64: upgrade to 8.0.32 or later (affected >= 8.0.0, <= 8.0.31)
• Microsoft.AspNetCore.App.Runtime.linux-x64 8.0.32Fixed version · GitHub Advisories · nuget package Microsoft.AspNetCore.App.Runtime.linux-x64: upgrade to 8.0.32 or later (affected >= 8.0.0, <= 8.0.31)
• Microsoft.AspNetCore.App.Runtime.osx-arm64 8.0.32Fixed version · GitHub Advisories · nuget package Microsoft.AspNetCore.App.Runtime.osx-arm64: upgrade to 8.0.32 or later (affected >= 8.0.0, <= 8.0.31)
• Microsoft.AspNetCore.App.Runtime.osx-x64 8.0.32Fixed version · GitHub Advisories · nuget package Microsoft.AspNetCore.App.Runtime.osx-x64: upgrade to 8.0.32 or later (affected >= 8.0.0, <= 8.0.31)
• Microsoft.AspNetCore.App.Runtime.win-arm64 8.0.32Fixed version · GitHub Advisories · nuget package Microsoft.AspNetCore.App.Runtime.win-arm64: upgrade to 8.0.32 or later (affected >= 8.0.0, <= 8.0.31)
• Microsoft.AspNetCore.App.Runtime.win-x64 8.0.32Fixed version · GitHub Advisories · nuget package Microsoft.AspNetCore.App.Runtime.win-x64: upgrade to 8.0.32 or later (affected >= 8.0.0, <= 8.0.31)
• Microsoft.AspNetCore.App.Runtime.win-x86 8.0.32Fixed version · GitHub Advisories · nuget package Microsoft.AspNetCore.App.Runtime.win-x86: upgrade to 8.0.32 or later (affected >= 8.0.0, <= 8.0.31)
• Microsoft.AspNetCore.App.Runtime.linux-arm 10.0.13Fixed version · GitHub Advisories · nuget package Microsoft.AspNetCore.App.Runtime.linux-arm: upgrade to 10.0.13 or later (affected >= 10.0.0, <= 10.0.12)
• Microsoft.AspNetCore.App.Runtime.linux-arm64 10.0.13Fixed version · GitHub Advisories · nuget package Microsoft.AspNetCore.App.Runtime.linux-arm64: upgrade to 10.0.13 or later (affected >= 10.0.0, <= 10.0.12)
• Microsoft.AspNetCore.App.Runtime.linux-musl-arm 10.0.13Fixed version · GitHub Advisories · nuget package Microsoft.AspNetCore.App.Runtime.linux-musl-arm: upgrade to 10.0.13 or later (affected >= 10.0.0, <= 10.0.12)
• Microsoft.AspNetCore.App.Runtime.linux-musl-arm64 10.0.13Fixed version · GitHub Advisories · nuget package Microsoft.AspNetCore.App.Runtime.linux-musl-arm64: upgrade to 10.0.13 or later (affected >= 10.0.0, <= 10.0.12)
• Microsoft.AspNetCore.App.Runtime.linux-musl-x64 10.0.13Fixed version · GitHub Advisories · nuget package Microsoft.AspNetCore.App.Runtime.linux-musl-x64: upgrade to 10.0.13 or later (affected >= 10.0.0, <= 10.0.12)
• Microsoft.AspNetCore.App.Runtime.linux-x64 10.0.13Fixed version · GitHub Advisories · nuget package Microsoft.AspNetCore.App.Runtime.linux-x64: upgrade to 10.0.13 or later (affected >= 10.0.0, <= 10.0.12)
• Microsoft.AspNetCore.App.Runtime.osx-arm64 10.0.13Fixed version · GitHub Advisories · nuget package Microsoft.AspNetCore.App.Runtime.osx-arm64: upgrade to 10.0.13 or later (affected >= 10.0.0, <= 10.0.12)
• Microsoft.AspNetCore.App.Runtime.osx-x64 10.0.13Fixed version · GitHub Advisories · nuget package Microsoft.AspNetCore.App.Runtime.osx-x64: upgrade to 10.0.13 or later (affected >= 10.0.0, <= 10.0.12)
• Microsoft.AspNetCore.App.Runtime.win-arm64 10.0.13Fixed version · GitHub Advisories · nuget package Microsoft.AspNetCore.App.Runtime.win-arm64: upgrade to 10.0.13 or later (affected >= 10.0.0, <= 10.0.12)
• Microsoft.AspNetCore.App.Runtime.win-x64 10.0.13Fixed version · GitHub Advisories · nuget package Microsoft.AspNetCore.App.Runtime.win-x64: upgrade to 10.0.13 or later (affected >= 10.0.0, <= 10.0.12)
• Microsoft.AspNetCore.App.Runtime.win-x86 10.0.13Fixed version · GitHub Advisories · nuget package Microsoft.AspNetCore.App.Runtime.win-x86: upgrade to 10.0.13 or later (affected >= 10.0.0, <= 10.0.12)
• Microsoft.AspNetCore.App.Runtime.linux-arm 11.0.0-rc.2Fixed version · GitHub Advisories · nuget package Microsoft.AspNetCore.App.Runtime.linux-arm: upgrade to 11.0.0-rc.2 or later (affected >= 11.0.0-preview.1, <= 11.0.0-rc.1)
• Microsoft.AspNetCore.App.Runtime.linux-arm64 11.0.0-rc.2Fixed version · GitHub Advisories · nuget package Microsoft.AspNetCore.App.Runtime.linux-arm64: upgrade to 11.0.0-rc.2 or later (affected >= 11.0.0-preview.1, <= 11.0.0-rc.1)
• Microsoft.AspNetCore.App.Runtime.linux-musl-arm 11.0.0-rc.2Fixed version · GitHub Advisories · nuget package Microsoft.AspNetCore.App.Runtime.linux-musl-arm: upgrade to 11.0.0-rc.2 or later (affected >= 11.0.0-preview.1, <= 11.0.0-rc.1)
• Microsoft.AspNetCore.App.Runtime.linux-musl-arm64 11.0.0-rc.2Fixed version · GitHub Advisories · nuget package Microsoft.AspNetCore.App.Runtime.linux-musl-arm64: upgrade to 11.0.0-rc.2 or later (affected >= 11.0.0-preview.1, <= 11.0.0-rc.1)
• Microsoft.AspNetCore.App.Runtime.linux-musl-x64 11.0.0-rc.2Fixed version · GitHub Advisories · nuget package Microsoft.AspNetCore.App.Runtime.linux-musl-x64: upgrade to 11.0.0-rc.2 or later (affected >= 11.0.0-preview.1, <= 11.0.0-rc.1)
• Microsoft.AspNetCore.App.Runtime.linux-x64 11.0.0-rc.2Fixed version · GitHub Advisories · nuget package Microsoft.AspNetCore.App.Runtime.linux-x64: upgrade to 11.0.0-rc.2 or later (affected >= 11.0.0-preview.1, <= 11.0.0-rc.1)
• Microsoft.AspNetCore.App.Runtime.osx-arm64 11.0.0-rc.2Fixed version · GitHub Advisories · nuget package Microsoft.AspNetCore.App.Runtime.osx-arm64: upgrade to 11.0.0-rc.2 or later (affected >= 11.0.0-preview.1, <= 11.0.0-rc.1)
• Microsoft.AspNetCore.App.Runtime.osx-x64 11.0.0-rc.2Fixed version · GitHub Advisories · nuget package Microsoft.AspNetCore.App.Runtime.osx-x64: upgrade to 11.0.0-rc.2 or later (affected >= 11.0.0-preview.1, <= 11.0.0-rc.1)
• Microsoft.AspNetCore.App.Runtime.win-arm64 11.0.0-rc.2Fixed version · GitHub Advisories · nuget package Microsoft.AspNetCore.App.Runtime.win-arm64: upgrade to 11.0.0-rc.2 or later (affected >= 11.0.0-preview.1, <= 11.0.0-rc.1)
• Microsoft.AspNetCore.App.Runtime.win-x64 11.0.0-rc.2Fixed version · GitHub Advisories · nuget package Microsoft.AspNetCore.App.Runtime.win-x64: upgrade to 11.0.0-rc.2 or later (affected >= 11.0.0-preview.1, <= 11.0.0-rc.1)
• Microsoft.AspNetCore.App.Runtime.win-x86 11.0.0-rc.2Fixed version · GitHub Advisories · nuget package Microsoft.AspNetCore.App.Runtime.win-x86: upgrade to 11.0.0-rc.2 or later (affected >= 11.0.0-preview.1, <= 11.0.0-rc.1)
• Microsoft.AspNetCore.App.Runtime.linux-arm 9.0.21Fixed version · GitHub Advisories · nuget package Microsoft.AspNetCore.App.Runtime.linux-arm: upgrade to 9.0.21 or later (affected >= 9.0.0, <= 9.0.20)
• Microsoft.AspNetCore.App.Runtime.linux-arm64 9.0.21Fixed version · GitHub Advisories · nuget package Microsoft.AspNetCore.App.Runtime.linux-arm64: upgrade to 9.0.21 or later (affected >= 9.0.0, <= 9.0.20)
• Microsoft.AspNetCore.App.Runtime.linux-musl-arm 9.0.21Fixed version · GitHub Advisories · nuget package Microsoft.AspNetCore.App.Runtime.linux-musl-arm: upgrade to 9.0.21 or later (affected >= 9.0.0, <= 9.0.20)
• Microsoft.AspNetCore.App.Runtime.linux-musl-arm64 9.0.21Fixed version · GitHub Advisories · nuget package Microsoft.AspNetCore.App.Runtime.linux-musl-arm64: upgrade to 9.0.21 or later (affected >= 9.0.0, <= 9.0.20)
• Microsoft.AspNetCore.App.Runtime.linux-musl-x64 9.0.21Fixed version · GitHub Advisories · nuget package Microsoft.AspNetCore.App.Runtime.linux-musl-x64: upgrade to 9.0.21 or later (affected >= 9.0.0, <= 9.0.20)
• Microsoft.AspNetCore.App.Runtime.linux-x64 9.0.21Fixed version · GitHub Advisories · nuget package Microsoft.AspNetCore.App.Runtime.linux-x64: upgrade to 9.0.21 or later (affected >= 9.0.0, <= 9.0.20)
• Microsoft.AspNetCore.App.Runtime.osx-arm64 9.0.21Fixed version · GitHub Advisories · nuget package Microsoft.AspNetCore.App.Runtime.osx-arm64: upgrade to 9.0.21 or later (affected >= 9.0.0, <= 9.0.20)
• Microsoft.AspNetCore.App.Runtime.osx-x64 9.0.21Fixed version · GitHub Advisories · nuget package Microsoft.AspNetCore.App.Runtime.osx-x64: upgrade to 9.0.21 or later (affected >= 9.0.0, <= 9.0.20)
• Microsoft.AspNetCore.App.Runtime.win-arm64 9.0.21Fixed version · GitHub Advisories · nuget package Microsoft.AspNetCore.App.Runtime.win-arm64: upgrade to 9.0.21 or later (affected >= 9.0.0, <= 9.0.20)
• Microsoft.AspNetCore.App.Runtime.win-x64 9.0.21Fixed version · GitHub Advisories · nuget package Microsoft.AspNetCore.App.Runtime.win-x64: upgrade to 9.0.21 or later (affected >= 9.0.0, <= 9.0.20)
• Microsoft.AspNetCore.App.Runtime.win-x86 9.0.21Fixed version · GitHub Advisories · nuget package Microsoft.AspNetCore.App.Runtime.win-x86: upgrade to 9.0.21 or later (affected >= 9.0.0, <= 9.0.20)

[ Advisories ]Government CERT advisories

• CERT-FR14 Oct 2026CERTFR-2026-AVI-1313

  Multiple vulnerabilities in Microsoft .Net Translated from French

  Multiple vulnerabilities have been discovered in Microsoft .Net. Some of them allow an attacker to cause remote arbitrary code execution, privilege escalation and remote denial of service.

  CVE-2026-70007CVE-2026-105016CVE-2026-96234+40 more CVEs
• CERT-FR14 Oct 2026CERTFR-2026-AVI-1316

  Multiple vulnerabilities in Microsoft products Translated from French

  Multiple vulnerabilities have been discovered in Microsoft products. Some of them allow an attacker to cause remote arbitrary code execution, privilege escalation and remote denial of service.

  CVE-2026-88086CVE-2026-70007CVE-2026-70179+141 more CVEs
• BSI CERT-Bund13 Oct 2026WID-SEC-2026-3893

  Microsoft Entwicklerwerkzeuge: Multiple vulnerabilities Translated from German

  Risk highCVE-2026-96230CVE-2026-84008CVE-2026-102238+64 more CVEs
• NCSC-NL13 Oct 2026NCSC-2026-0426

  Vulnerabilities fixed in Microsoft Developer Tools Translated from Dutch

  Probability/damage M/HCVE-2026-58280CVE-2026-66822CVE-2026-69370+59 more CVEs
• NCSC-NL13 Oct 2026NCSC-2026-0423

  Vulnerabilities fixed in Microsoft Windows Translated from Dutch

  Probability/damage M/HCVE-2026-100202CVE-2026-100219CVE-2026-100222+49 more CVEs

[ Packages ]Affected open-source packages

• Microsoft.AspNetCore.App.Runtime.linux-arm nugetAffected >= 8.0.0, <= 8.0.31 · fixed in 8.0.32 · GHSA-rv87-ccxw-8ggf
• Microsoft.AspNetCore.App.Runtime.linux-arm64 nugetAffected >= 8.0.0, <= 8.0.31 · fixed in 8.0.32 · GHSA-rv87-ccxw-8ggf
• Microsoft.AspNetCore.App.Runtime.linux-musl-arm nugetAffected >= 8.0.0, <= 8.0.31 · fixed in 8.0.32 · GHSA-rv87-ccxw-8ggf
• Microsoft.AspNetCore.App.Runtime.linux-musl-arm64 nugetAffected >= 8.0.0, <= 8.0.31 · fixed in 8.0.32 · GHSA-rv87-ccxw-8ggf
• Microsoft.AspNetCore.App.Runtime.linux-musl-x64 nugetAffected >= 8.0.0, <= 8.0.31 · fixed in 8.0.32 · GHSA-rv87-ccxw-8ggf
• Microsoft.AspNetCore.App.Runtime.linux-x64 nugetAffected >= 8.0.0, <= 8.0.31 · fixed in 8.0.32 · GHSA-rv87-ccxw-8ggf
• Microsoft.AspNetCore.App.Runtime.osx-arm64 nugetAffected >= 8.0.0, <= 8.0.31 · fixed in 8.0.32 · GHSA-rv87-ccxw-8ggf
• Microsoft.AspNetCore.App.Runtime.osx-x64 nugetAffected >= 8.0.0, <= 8.0.31 · fixed in 8.0.32 · GHSA-rv87-ccxw-8ggf
• Microsoft.AspNetCore.App.Runtime.win-arm64 nugetAffected >= 8.0.0, <= 8.0.31 · fixed in 8.0.32 · GHSA-rv87-ccxw-8ggf
• Microsoft.AspNetCore.App.Runtime.win-x64 nugetAffected >= 8.0.0, <= 8.0.31 · fixed in 8.0.32 · GHSA-rv87-ccxw-8ggf
• Microsoft.AspNetCore.App.Runtime.win-x86 nugetAffected >= 8.0.0, <= 8.0.31 · fixed in 8.0.32 · GHSA-rv87-ccxw-8ggf
• Microsoft.AspNetCore.App.Runtime.linux-arm nugetAffected >= 10.0.0, <= 10.0.12 · fixed in 10.0.13 · GHSA-rv87-ccxw-8ggf
• Microsoft.AspNetCore.App.Runtime.linux-arm64 nugetAffected >= 10.0.0, <= 10.0.12 · fixed in 10.0.13 · GHSA-rv87-ccxw-8ggf
• Microsoft.AspNetCore.App.Runtime.linux-musl-arm nugetAffected >= 10.0.0, <= 10.0.12 · fixed in 10.0.13 · GHSA-rv87-ccxw-8ggf
• Microsoft.AspNetCore.App.Runtime.linux-musl-arm64 nugetAffected >= 10.0.0, <= 10.0.12 · fixed in 10.0.13 · GHSA-rv87-ccxw-8ggf
• Microsoft.AspNetCore.App.Runtime.linux-musl-x64 nugetAffected >= 10.0.0, <= 10.0.12 · fixed in 10.0.13 · GHSA-rv87-ccxw-8ggf
• Microsoft.AspNetCore.App.Runtime.linux-x64 nugetAffected >= 10.0.0, <= 10.0.12 · fixed in 10.0.13 · GHSA-rv87-ccxw-8ggf
• Microsoft.AspNetCore.App.Runtime.osx-arm64 nugetAffected >= 10.0.0, <= 10.0.12 · fixed in 10.0.13 · GHSA-rv87-ccxw-8ggf
• Microsoft.AspNetCore.App.Runtime.osx-x64 nugetAffected >= 10.0.0, <= 10.0.12 · fixed in 10.0.13 · GHSA-rv87-ccxw-8ggf
• Microsoft.AspNetCore.App.Runtime.win-arm64 nugetAffected >= 10.0.0, <= 10.0.12 · fixed in 10.0.13 · GHSA-rv87-ccxw-8ggf
• Microsoft.AspNetCore.App.Runtime.win-x64 nugetAffected >= 10.0.0, <= 10.0.12 · fixed in 10.0.13 · GHSA-rv87-ccxw-8ggf
• Microsoft.AspNetCore.App.Runtime.win-x86 nugetAffected >= 10.0.0, <= 10.0.12 · fixed in 10.0.13 · GHSA-rv87-ccxw-8ggf
• Microsoft.AspNetCore.App.Runtime.linux-arm nugetAffected >= 11.0.0-preview.1, <= 11.0.0-rc.1 · fixed in 11.0.0-rc.2 · GHSA-rv87-ccxw-8ggf
• Microsoft.AspNetCore.App.Runtime.linux-arm64 nugetAffected >= 11.0.0-preview.1, <= 11.0.0-rc.1 · fixed in 11.0.0-rc.2 · GHSA-rv87-ccxw-8ggf
• Microsoft.AspNetCore.App.Runtime.linux-musl-arm nugetAffected >= 11.0.0-preview.1, <= 11.0.0-rc.1 · fixed in 11.0.0-rc.2 · GHSA-rv87-ccxw-8ggf
• Microsoft.AspNetCore.App.Runtime.linux-musl-arm64 nugetAffected >= 11.0.0-preview.1, <= 11.0.0-rc.1 · fixed in 11.0.0-rc.2 · GHSA-rv87-ccxw-8ggf
• Microsoft.AspNetCore.App.Runtime.linux-musl-x64 nugetAffected >= 11.0.0-preview.1, <= 11.0.0-rc.1 · fixed in 11.0.0-rc.2 · GHSA-rv87-ccxw-8ggf
• Microsoft.AspNetCore.App.Runtime.linux-x64 nugetAffected >= 11.0.0-preview.1, <= 11.0.0-rc.1 · fixed in 11.0.0-rc.2 · GHSA-rv87-ccxw-8ggf
• Microsoft.AspNetCore.App.Runtime.osx-arm64 nugetAffected >= 11.0.0-preview.1, <= 11.0.0-rc.1 · fixed in 11.0.0-rc.2 · GHSA-rv87-ccxw-8ggf
• Microsoft.AspNetCore.App.Runtime.osx-x64 nugetAffected >= 11.0.0-preview.1, <= 11.0.0-rc.1 · fixed in 11.0.0-rc.2 · GHSA-rv87-ccxw-8ggf
• Microsoft.AspNetCore.App.Runtime.win-arm64 nugetAffected >= 11.0.0-preview.1, <= 11.0.0-rc.1 · fixed in 11.0.0-rc.2 · GHSA-rv87-ccxw-8ggf
• Microsoft.AspNetCore.App.Runtime.win-x64 nugetAffected >= 11.0.0-preview.1, <= 11.0.0-rc.1 · fixed in 11.0.0-rc.2 · GHSA-rv87-ccxw-8ggf
• Microsoft.AspNetCore.App.Runtime.win-x86 nugetAffected >= 11.0.0-preview.1, <= 11.0.0-rc.1 · fixed in 11.0.0-rc.2 · GHSA-rv87-ccxw-8ggf
• Microsoft.AspNetCore.App.Runtime.linux-arm nugetAffected >= 9.0.0, <= 9.0.20 · fixed in 9.0.21 · GHSA-rv87-ccxw-8ggf
• Microsoft.AspNetCore.App.Runtime.linux-arm64 nugetAffected >= 9.0.0, <= 9.0.20 · fixed in 9.0.21 · GHSA-rv87-ccxw-8ggf
• Microsoft.AspNetCore.App.Runtime.linux-musl-arm nugetAffected >= 9.0.0, <= 9.0.20 · fixed in 9.0.21 · GHSA-rv87-ccxw-8ggf
• Microsoft.AspNetCore.App.Runtime.linux-musl-arm64 nugetAffected >= 9.0.0, <= 9.0.20 · fixed in 9.0.21 · GHSA-rv87-ccxw-8ggf
• Microsoft.AspNetCore.App.Runtime.linux-musl-x64 nugetAffected >= 9.0.0, <= 9.0.20 · fixed in 9.0.21 · GHSA-rv87-ccxw-8ggf
• Microsoft.AspNetCore.App.Runtime.linux-x64 nugetAffected >= 9.0.0, <= 9.0.20 · fixed in 9.0.21 · GHSA-rv87-ccxw-8ggf
• Microsoft.AspNetCore.App.Runtime.osx-arm64 nugetAffected >= 9.0.0, <= 9.0.20 · fixed in 9.0.21 · GHSA-rv87-ccxw-8ggf
• Microsoft.AspNetCore.App.Runtime.osx-x64 nugetAffected >= 9.0.0, <= 9.0.20 · fixed in 9.0.21 · GHSA-rv87-ccxw-8ggf
• Microsoft.AspNetCore.App.Runtime.win-arm64 nugetAffected >= 9.0.0, <= 9.0.20 · fixed in 9.0.21 · GHSA-rv87-ccxw-8ggf
• Microsoft.AspNetCore.App.Runtime.win-x64 nugetAffected >= 9.0.0, <= 9.0.20 · fixed in 9.0.21 · GHSA-rv87-ccxw-8ggf
• Microsoft.AspNetCore.App.Runtime.win-x86 nugetAffected >= 9.0.0, <= 9.0.20 · fixed in 9.0.21 · GHSA-rv87-ccxw-8ggf

[ References ]References

• msrc.microsoft.com/update-guide/vulnerability/CVE-2026-88092PatchVendor Advisory