Vulnerability · CVE-2026-96236

Microsoft Security Advisory CVE-2026-96236 - ASP.NET Core Denial of Service Vulnerability

Published Oct 13, 2026 · catalog updated Oct 19, 2026 · Microsoft Security Advisory -

Open the advisory

Exploitation likelihood is not on this record for CVE-2026-96236. A missing EPSS score is not a low risk. Compare Microsoft Security Advisory - with the linked advisory before you change production.

Gaps on this record

The stored product name is a package slug. The name on this page is taken from the title (Microsoft Security Advisory -).
No vendor fix or required action is stored. Compare the linked advisory before you change production.
EPSS is missing. A missing score is not a low risk.

Severity: High7.5
Known exploitation: Not in CISA/VulnCheck KEV
EPSS: Awaiting synchronization with FIRST
Remediation: Advisory link
Affected products: NuGet Microsoft.AspNetCore.App.Runtime.linux-arm · NuGet Microsoft.AspNetCore.App.Runtime.linux-arm64 · NuGet Microsoft.AspNetCore.App.Runtime.linux-musl-arm · NuGet Microsoft.AspNetCore.App.Runtime.linux-musl-arm64 · NuGet Microsoft.AspNetCore.App.Runtime.linux-musl-x64 · NuGet Microsoft.AspNetCore.App.Runtime.linux-x64

## Executive summary Microsoft is releasing this security advisory to provide information about a vulnerability in Microsoft.AspNetCore.Localization. This advisory also provides guidance on what developers can do to update their applications to remove this vulnerability. ASP.NET Core request-localization fallback can add attacker-supplied synthetic culture names to the runtime's global cache, allowing unauthenticated requests to cause unbounded memory growth and denial of service. ## Announcement Announcement for this issue can be found at https://github.com/dotnet/announcements/issues/484 ## CVSS Details - **Version:** 3.1 - **Severity:** High - **Score:** 7.5 - **Vector:** - **Weakness:** CWE-770 (Allocation of Resources Without Limits or Throttling) ## Affected Platforms - **Platforms:** Windows, Linux, macOS - **Architectures:** All ## 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, = 8.0.0, = 8.0.0, = 8.0.0, = 8.0.0, = 8.0.0, = 8.0.0, = 8.0.0, = 8.0.0, = 8.0.0, = 8.0.0, = 8.0.0, = 11.0.0-preview.1, = 11.0.0-preview.1, = 11.0.0-preview.1, = 11.0.0-preview.1, = 11.0.0-preview.1, = 11.0.0-preview.1, = 11.0.0-preview.1, = 11.0.0-preview.1, = 11.0.0-preview.1, = 11.0.0-preview.1, = 11.0.0-preview.1, = 11.0.0-preview.1, = 10.0.0, = 10.0.0, = 10.0.0, = 10.0.0, = 10.0.0, = 10.0.0, = 10.0.0, = 10.0.0, = 10.0.0, = 10.0.0, = 10.0.0, = 10.0.0, = 9.0.0, = 9.0.0, = 9.0.0, = 9.0.0, = 9.0.0, = 9.0.0, = 9.0.0, = 9.0.0, = 9.0.0, = 9.0.0, = 9.0.0, = 9.0.0, How do I know if I am affected? If using a package listed in [affected packages](#affected-packages), you're exposed to the vulnerability. ### How do I fix the issue? 1. To fix the issue please install the latest version of .NET.

Are you affected?

Enter the version you run. The result uses only the ranges stored on this record.

The check returns affected, not affected, or incomplete. It does not guess a version that is missing from the record.

NuGet Microsoft.AspNetCore.App.Runtime.linux-arm11.0.0-preview.1 → 11.0.0-rc.2
NuGet Microsoft.AspNetCore.App.Runtime.linux-arm8.0.0 → 8.0.32
NuGet Microsoft.AspNetCore.App.Runtime.linux-arm648.0.0 → 8.0.32
NuGet Microsoft.AspNetCore.App.Runtime.linux-musl-arm8.0.0 → 8.0.32
NuGet Microsoft.AspNetCore.App.Runtime.linux-musl-arm648.0.0 → 8.0.32
NuGet Microsoft.AspNetCore.App.Runtime.linux-musl-x648.0.0 → 8.0.32
NuGet Microsoft.AspNetCore.App.Runtime.linux-x648.0.0 → 8.0.32
NuGet Microsoft.AspNetCore.App.Runtime.osx-arm648.0.0 → 8.0.32
NuGet Microsoft.AspNetCore.App.Runtime.osx-x648.0.0 → 8.0.32
NuGet Microsoft.AspNetCore.App.Runtime.win-arm648.0.0 → 8.0.32
NuGet Microsoft.AspNetCore.App.Runtime.win-x648.0.0 → 8.0.32
NuGet Microsoft.AspNetCore.App.Runtime.win-x868.0.0 → 8.0.32

How to fix CVE-2026-96236

Recommended remediation
A patch or advisory reference is linked. Open the original publisher for availability by product version.
Official advisories
- GitHub Advisory Database · github.com
- OpenSSF OSV / OSV Scanner · osv.dev

What to do

Three questions, each answered from this record only. Confirm the vendor advisory before you patch.

Should you patch?

Exploitation likelihood is not on this record for CVE-2026-96236. A missing EPSS score is not a low risk. Compare Microsoft Security Advisory - with the linked advisory before you change production.

Which versions are affected?

Compare what you have installed with Microsoft.AspNetCore.App.Runtime.linux-arm 11.0.0-preview.1 → 11.0.0-rc.2; Microsoft.AspNetCore.App.Runtime.linux-arm 8.0.0 → 8.0.32; Microsoft.AspNetCore.App.Runtime.linux-arm64 8.0.0 → 8.0.32; Microsoft.AspNetCore.App.Runtime.linux-musl-arm 8.0.0 → 8.0.32. Compare the installed version with the linked vendor advisory before you change production.

What should an analyst verify?

CWE-770: Allocation of Resources Without Limits or Throttling. EPSS is not on this record yet. There is no CISA KEV listing. No Exploit-DB or Metasploit reference is linked. Use the source links for the original advisory.

Code

The project this record applies to. Exploit listings stay in References.

Timeline

Detection, updates, and resolution for this record.

Oct 13, 2026 · GitHub Advisory Database
Detected
## Executive summary Microsoft is releasing this security advisory to provide information about a vulnerability in Microsoft.AspNetCore.Localization. This advisory also provides guidance on what developers can do to update their applications to remove this vulnerability. ASP.NET Core request-localization fallback can add attacker-supplied synthetic culture names to the runtime's global cache, allo
Oct 19, 2026 · GitHub Advisory Database
Fix available
Microsoft.AspNetCore.App.Runtime.linux-arm fixed in 8.0.32; Microsoft.AspNetCore.App.Runtime.linux-arm64 fixed in 8.0.32; Microsoft.AspNetCore.App.Runtime.linux-musl-arm fixed in 8.0.32; Microsoft.AspNetCore.App.Runtime.linux-musl-arm64 fixed in 8.0.32
Oct 19, 2026 · GitHub Advisory Database
Fix available
Microsoft.AspNetCore.App.Runtime.linux-arm fixed in 8.0.32
Oct 19, 2026 · GitHub Advisory Database
Fix available
Microsoft.AspNetCore.App.Runtime.linux-arm64 fixed in 8.0.32
Oct 19, 2026 · GitHub Advisory Database
Fix available
Microsoft.AspNetCore.App.Runtime.linux-musl-arm fixed in 8.0.32
Oct 19, 2026 · GitHub Advisory Database
Fix available
Microsoft.AspNetCore.App.Runtime.linux-musl-arm64 fixed in 8.0.32
Oct 19, 2026 · GitHub Advisory Database
Fix available
Microsoft.AspNetCore.App.Runtime.linux-musl-x64 fixed in 8.0.32
Oct 19, 2026 · GitHub Advisory Database
Fix available
Microsoft.AspNetCore.App.Runtime.linux-x64 fixed in 8.0.32
Oct 19, 2026 · GitHub Advisory Database
Fix available
Microsoft.AspNetCore.App.Runtime.osx-arm64 fixed in 8.0.32
Oct 19, 2026 · GitHub Advisory Database
Fix available
Microsoft.AspNetCore.App.Runtime.osx-x64 fixed in 8.0.32
Oct 19, 2026 · GitHub Advisory Database
Fix available
Microsoft.AspNetCore.App.Runtime.win-arm64 fixed in 8.0.32
Oct 19, 2026 · GitHub Advisory Database
Fix available
Microsoft.AspNetCore.App.Runtime.win-x64 fixed in 8.0.32
Oct 19, 2026 · GitHub Advisory Database
Fix available
Microsoft.AspNetCore.App.Runtime.win-x86 fixed in 8.0.32
Oct 19, 2026 · GitHub Advisory Database
Fix available
Microsoft.AspNetCore.App.Runtime.linux-arm fixed in 11.0.0-rc.2
Oct 19, 2026 · GitHub Advisory Database
Updated
## Executive summary Microsoft is releasing this security advisory to provide information about a vulnerability in Microsoft.AspNetCore.Localization. This advisory also provides guidance on what developers can do to update their applications to remove this vulnerability. ASP.NET Core request-localization fallback can add attacker-supplied synthetic culture names to the runtime's global cache, allo

Sources

GitHub Advisory DatabasePackage advisoryGHSA-f4g7-52wc-p8x7
GitHub Advisory Database record mirrored by OSV.
github.com
OpenSSF OSV / OSV ScannerPackage advisoryGHSA-f4g7-52wc-p8x7
Microsoft Security Advisory CVE-2026-96236 - ASP.NET Core Denial of Service Vulnerability
osv.dev

References

Freshness

Last verified in this catalog Oct 19, 2026. Significant claims (KEV, EPSS, CVSS, affected ranges) come from the source rows above — open the original publisher for the authoritative advisory.

Priority score

11/100

Evidence confidence: Medium

One connected source supports this record.

Confirmed exploitation0/30
EPSS probability0/20
CVSS severity11/15
Public exploit0/10
Internet exposure0/10
Product prevalence0/5
Threat research0/5

Decision signals

Four separate signals — do not infer one from another.

High

CVSS severity
7.5 v3.1
Technical impact. Separate from exploitation likelihood.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS probability
—
Awaiting synchronization with FIRST
Known exploitation
No verified KEV listing
Evidence from CISA KEV or VulnCheck KEV only — not from EPSS alone.
Patch availability
Advisory link
A patch or advisory reference is linked. Open the original publisher for availability by product version.

Stacks

Microsoft NuGet

Weakness

CWE-770
Allocation of Resources Without Limits or Throttling
MITRE definition

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