criticalCVSS 9.4Vulnerability

CVE-2026-88092

## Executive summary Microsoft is releasing this security advisory to provide information about a vulnerability in Microsoft.AspNetCore.Server.Kestrel.Core. This advisory also provides guidance on what developers can do to update their applications to remove this vulnerability. An aborted Kestrel HTTP/1 connection can reparse unread request-body bytes as another request, creating a request-smuggling or desynchronization path. ## Announcement Announcement for this issue can be found at https://github.com/dotnet/announcements/issues/472 ## CVSS Details - **Version:** 3.1 - **Severity:** Critical - **Score:** 9.4 - **Vector:** `CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:L` - **Weakness:** CWE-444 (Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')) ## Affected Platforms - **Platforms:** Windows, Linux, macOS - **Architectures:** All ## <a name="affected-packages"></a>Affected Packages The vulnerability affects Microsoft .NET projects that use an affected package version listed below. Package name | Affected version | Patched version ------------ | ---------------- | --------------- [Microsoft.AspNetCore.App.Runtime.linux-arm](https://www.nuget.org/packages/Microsoft.AspNetCore.App.Runtime.linux-arm) | >= 8.0.0, <= 8.0.31 | 8.0.32 [Microsoft.AspNetCore.App.Runtime.linux-arm64](https://www.nuget.org/packages/Microsoft.AspNetCore.App.Runtime.linux-arm64) | >= 8.0.0, <= 8.0.31 | 8.0.32 [Microsoft.AspNetCore.App.Runtime.linux-musl-arm](https://www.nuget.org/packages/Microsoft.AspNetCore.App.Runtime.linux-musl-arm) | >= 8.0.0, <= 8.0.31 | 8.0.32 [Microsoft.AspNetCore.App.Runtime.linux-musl-arm64](https://www.nuget.org/packages/Microsoft.AspNetCore.App.Runtime.linux-musl-arm64) | >= 8.0.0, <= 8.0.31 | 8.0.32 [Microsoft.AspNetCore.App.Runtime.linux-musl-x64](https://www.nuget.org/packages/Microsoft.AspNetCore.App.Runtime.linux-musl-x64) | >= 8.0.0, <= 8.0.31 | 8.0.32 [Microsoft.AspNetCore.App.Runtime.linux-x64](https://www.nuget.org/pac

Properties

severity
critical
summary
Microsoft Security Advisory CVE-2026-88092 - ASP.NET Core Security Feature Bypass Vulnerability
cvss_score
9.4
retrieved_at
2026-10-14T00:18:40+00:00
ghsa_published
2026-10-13T20:40:50Z
source_url
https://github.com/advisories/GHSA-rv87-ccxw-8ggf
ghsa_updated
2026-10-13T20:40:53Z
ghsa_id
GHSA-rv87-ccxw-8ggf
last_source
GitHub Advisory Database
cve_id
CVE-2026-88092
cvss_vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:L
signal_observed_at
2026-10-14T00:11:18+00:00
is_ghsa_only
false

Related Entities (24)

HAS_WEAKNESS (1)

→[Weakness]Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')

REPORTED_BY (1)

→[Source]GitHub Advisory Database

VULNERABLE_TO (11)

←[Software]nuget/Microsoft.AspNetCore.App.Runtime.linux-musl-x64
←[Software]nuget/Microsoft.AspNetCore.App.Runtime.osx-x64
←[Software]nuget/Microsoft.AspNetCore.App.Runtime.osx-arm64
←[Software]nuget/Microsoft.AspNetCore.App.Runtime.linux-musl-arm64
←[Software]nuget/Microsoft.AspNetCore.App.Runtime.win-arm64
←[Software]nuget/Microsoft.AspNetCore.App.Runtime.win-x86
←[Software]nuget/Microsoft.AspNetCore.App.Runtime.win-x64
←[Software]nuget/Microsoft.AspNetCore.App.Runtime.linux-musl-arm
←[Software]nuget/Microsoft.AspNetCore.App.Runtime.linux-x64
←[Software]nuget/Microsoft.AspNetCore.App.Runtime.linux-arm64
←[Software]nuget/Microsoft.AspNetCore.App.Runtime.linux-arm

AFFECTS (11)

→[Software]nuget/Microsoft.AspNetCore.App.Runtime.linux-musl-x64
→[Software]nuget/Microsoft.AspNetCore.App.Runtime.linux-x64
→[Software]nuget/Microsoft.AspNetCore.App.Runtime.win-arm64
→[Software]nuget/Microsoft.AspNetCore.App.Runtime.osx-arm64
→[Software]nuget/Microsoft.AspNetCore.App.Runtime.linux-musl-arm
→[Software]nuget/Microsoft.AspNetCore.App.Runtime.osx-x64
→[Software]nuget/Microsoft.AspNetCore.App.Runtime.win-x64
→[Software]nuget/Microsoft.AspNetCore.App.Runtime.win-x86
→[Software]nuget/Microsoft.AspNetCore.App.Runtime.linux-arm
→[Software]nuget/Microsoft.AspNetCore.App.Runtime.linux-arm64
→[Software]nuget/Microsoft.AspNetCore.App.Runtime.linux-musl-arm64

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CVE-2026-88092 (CVSS 9.4) — Ninja Signal Threat Intelligence | Ninja Signal