---
title: "CVE-2026-88092: Microsoft Security Advisory CVE-2026-88092 - ASP.NET Core Security Feature Bypass Vulnerability"
url: https://erroneo.us/security/cve/CVE-2026-88092/
description: "CVE-2026-88092 (Microsoft.AspNetCore.App.Runtime.linux-arm (NuGet)): Inconsistent interpretation of http requests ('http request/response smuggling') in…"
type: vulnerability-record
section: "Security Digest"
date_published: 2026-10-13
date_modified: 2026-10-21
publisher: erroneo.us
author: erroneo.us Security Desk
cve: "CVE-2026-88092"
kev: false
cvss: 9.4
epss: 0.00786
license: All rights reserved. Quote with attribution and a link.
---

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

**Signal:** Critical and remotely reachable. No known exploitation yet, but it is network-reachable without credentials. (Computed from CISA KEV, EPSS and CVSS; not an editorial verdict.)

## Should you act?

- No confirmed exploitation. It is not in CISA’s KEV catalog and CISA’s SSVC assessment records no known exploitation. That can change quickly after a public write-up; re-check if you are affected.
- EPSS 0.8% , percentile 56: FIRST’s model estimates a 0.8% chance of exploitation activity in the next 30 days, higher than 56% of all scored CVEs (moderate). EPSS is a probability, not a verdict.
- Remotely reachable with no login and no user interaction. If the vulnerable service is exposed to the internet, prioritize it.
- Only applies if your dependency tree includes Microsoft.AspNetCore.App.Runtime.linux-arm (NuGet) >= 8.0.0, <= 8.0.31, fixed in 8.0.32 ; Microsoft.AspNetCore.App.Runtime.linux-arm64 (NuGet) >= 8.0.0, <= 8.0.31, fixed in 8.0.32 ; Microsoft.AspNetCore.App.Runtime.linux-musl-arm (NuGet) >= 8.0.0, <= 8.0.31, fixed in 8.0.32 ; Microsoft.AspNetCore.App.Runtime.linux-musl-arm64 (NuGet) >= 8.0.0, <= 8.0.31, fixed in 8.0.32 . Check your lockfile, including transitive dependencies.

## What it is

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

## Affected packages

- NuGet `Microsoft.AspNetCore.App.Runtime.linux-arm` >= 8.0.0, <= 8.0.31 → fixed: 8.0.32
- NuGet `Microsoft.AspNetCore.App.Runtime.linux-arm64` >= 8.0.0, <= 8.0.31 → fixed: 8.0.32
- NuGet `Microsoft.AspNetCore.App.Runtime.linux-musl-arm` >= 8.0.0, <= 8.0.31 → fixed: 8.0.32
- NuGet `Microsoft.AspNetCore.App.Runtime.linux-musl-arm64` >= 8.0.0, <= 8.0.31 → fixed: 8.0.32
- NuGet `Microsoft.AspNetCore.App.Runtime.linux-musl-x64` >= 8.0.0, <= 8.0.31 → fixed: 8.0.32
- NuGet `Microsoft.AspNetCore.App.Runtime.linux-x64` >= 8.0.0, <= 8.0.31 → fixed: 8.0.32
- NuGet `Microsoft.AspNetCore.App.Runtime.osx-arm64` >= 8.0.0, <= 8.0.31 → fixed: 8.0.32
- NuGet `Microsoft.AspNetCore.App.Runtime.osx-x64` >= 8.0.0, <= 8.0.31 → fixed: 8.0.32
- NuGet `Microsoft.AspNetCore.App.Runtime.win-arm64` >= 8.0.0, <= 8.0.31 → fixed: 8.0.32
- NuGet `Microsoft.AspNetCore.App.Runtime.win-x64` >= 8.0.0, <= 8.0.31 → fixed: 8.0.32
- NuGet `Microsoft.AspNetCore.App.Runtime.win-x86` >= 8.0.0, <= 8.0.31 → fixed: 8.0.32
- NuGet `Microsoft.AspNetCore.App.Runtime.linux-arm` >= 10.0.0, <= 10.0.12 → fixed: 10.0.13
- NuGet `Microsoft.AspNetCore.App.Runtime.linux-arm64` >= 10.0.0, <= 10.0.12 → fixed: 10.0.13
- NuGet `Microsoft.AspNetCore.App.Runtime.linux-musl-arm` >= 10.0.0, <= 10.0.12 → fixed: 10.0.13
- NuGet `Microsoft.AspNetCore.App.Runtime.linux-musl-arm64` >= 10.0.0, <= 10.0.12 → fixed: 10.0.13
- NuGet `Microsoft.AspNetCore.App.Runtime.linux-musl-x64` >= 10.0.0, <= 10.0.12 → fixed: 10.0.13
- NuGet `Microsoft.AspNetCore.App.Runtime.linux-x64` >= 10.0.0, <= 10.0.12 → fixed: 10.0.13
- NuGet `Microsoft.AspNetCore.App.Runtime.osx-arm64` >= 10.0.0, <= 10.0.12 → fixed: 10.0.13
- NuGet `Microsoft.AspNetCore.App.Runtime.osx-x64` >= 10.0.0, <= 10.0.12 → fixed: 10.0.13
- NuGet `Microsoft.AspNetCore.App.Runtime.win-arm64` >= 10.0.0, <= 10.0.12 → fixed: 10.0.13
- NuGet `Microsoft.AspNetCore.App.Runtime.win-x64` >= 10.0.0, <= 10.0.12 → fixed: 10.0.13
- NuGet `Microsoft.AspNetCore.App.Runtime.win-x86` >= 10.0.0, <= 10.0.12 → fixed: 10.0.13
- NuGet `Microsoft.AspNetCore.App.Runtime.linux-arm` >= 11.0.0-preview.1, <= 11.0.0-rc.1 → fixed: 11.0.0-rc.2
- NuGet `Microsoft.AspNetCore.App.Runtime.linux-arm64` >= 11.0.0-preview.1, <= 11.0.0-rc.1 → fixed: 11.0.0-rc.2
- NuGet `Microsoft.AspNetCore.App.Runtime.linux-musl-arm` >= 11.0.0-preview.1, <= 11.0.0-rc.1 → fixed: 11.0.0-rc.2
- NuGet `Microsoft.AspNetCore.App.Runtime.linux-musl-arm64` >= 11.0.0-preview.1, <= 11.0.0-rc.1 → fixed: 11.0.0-rc.2
- NuGet `Microsoft.AspNetCore.App.Runtime.linux-musl-x64` >= 11.0.0-preview.1, <= 11.0.0-rc.1 → fixed: 11.0.0-rc.2
- NuGet `Microsoft.AspNetCore.App.Runtime.linux-x64` >= 11.0.0-preview.1, <= 11.0.0-rc.1 → fixed: 11.0.0-rc.2
- NuGet `Microsoft.AspNetCore.App.Runtime.osx-arm64` >= 11.0.0-preview.1, <= 11.0.0-rc.1 → fixed: 11.0.0-rc.2
- NuGet `Microsoft.AspNetCore.App.Runtime.osx-x64` >= 11.0.0-preview.1, <= 11.0.0-rc.1 → fixed: 11.0.0-rc.2
- NuGet `Microsoft.AspNetCore.App.Runtime.win-arm64` >= 11.0.0-preview.1, <= 11.0.0-rc.1 → fixed: 11.0.0-rc.2
- NuGet `Microsoft.AspNetCore.App.Runtime.win-x64` >= 11.0.0-preview.1, <= 11.0.0-rc.1 → fixed: 11.0.0-rc.2
- NuGet `Microsoft.AspNetCore.App.Runtime.win-x86` >= 11.0.0-preview.1, <= 11.0.0-rc.1 → fixed: 11.0.0-rc.2
- NuGet `Microsoft.AspNetCore.App.Runtime.linux-arm` >= 9.0.0, <= 9.0.20 → fixed: 9.0.21
- NuGet `Microsoft.AspNetCore.App.Runtime.linux-arm64` >= 9.0.0, <= 9.0.20 → fixed: 9.0.21
- NuGet `Microsoft.AspNetCore.App.Runtime.linux-musl-arm` >= 9.0.0, <= 9.0.20 → fixed: 9.0.21
- NuGet `Microsoft.AspNetCore.App.Runtime.linux-musl-arm64` >= 9.0.0, <= 9.0.20 → fixed: 9.0.21
- NuGet `Microsoft.AspNetCore.App.Runtime.linux-musl-x64` >= 9.0.0, <= 9.0.20 → fixed: 9.0.21
- NuGet `Microsoft.AspNetCore.App.Runtime.linux-x64` >= 9.0.0, <= 9.0.20 → fixed: 9.0.21
- NuGet `Microsoft.AspNetCore.App.Runtime.osx-arm64` >= 9.0.0, <= 9.0.20 → fixed: 9.0.21
- NuGet `Microsoft.AspNetCore.App.Runtime.osx-x64` >= 9.0.0, <= 9.0.20 → fixed: 9.0.21
- NuGet `Microsoft.AspNetCore.App.Runtime.win-arm64` >= 9.0.0, <= 9.0.20 → fixed: 9.0.21
- NuGet `Microsoft.AspNetCore.App.Runtime.win-x64` >= 9.0.0, <= 9.0.20 → fixed: 9.0.21
- NuGet `Microsoft.AspNetCore.App.Runtime.win-x86` >= 9.0.0, <= 9.0.20 → fixed: 9.0.21

## Affected products (CVE record)

- Microsoft ASP.NET Core 10.0: 10.0 < 10.0.13
- Microsoft ASP.NET Core 11.0: 11.0 < 11.0.0-rc.2
- Microsoft ASP.NET Core 8.0: 8.0 < 8.0.32
- Microsoft ASP.NET Core 9.0: 9.0 < 9.0.21
- Microsoft Microsoft Visual Studio 2022 version 17.14: 17.14.0 < 17.14.42
- Microsoft Microsoft Visual Studio 2026 version 18.10: 18.10.0 < 18.10.4

## Severity

- microsoft CVSS 3.1: 9.4 `CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:L/E:U/RL:O/RC:C`
- GitHub CVSS 3.1: 9.4 `CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:L`

## Exploitation

- CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
- CISA SSVC assessment: exploitation none , automatable yes , technical impact total .
- FIRST EPSS (model of 2026-10-21): 0.79% probability of exploitation activity in the next 30 days; percentile 56.

## Sources

- [ASP.NET Core Tampering Vulnerability](https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-88092)
- [GitHub Advisory GHSA-rv87-ccxw-8ggf](https://github.com/advisories/GHSA-rv87-ccxw-8ggf)
- [CVE.org record CVE-2026-88092](https://www.cve.org/CVERecord?id=CVE-2026-88092)
- [NVD entry CVE-2026-88092](https://nvd.nist.gov/vuln/detail/CVE-2026-88092)
- [github.com](https://github.com/dotnet/aspnetcore/security/advisories/GHSA-rv87-ccxw-8ggf)
- [github.com](https://github.com/dotnet/announcements/issues/472)

---
Source page: https://erroneo.us/security/cve/CVE-2026-88092/ · Security Digest: https://erroneo.us/security/ · More: https://erroneo.us/llms.txt