Microsoft Security Advisory CVE-2026-32175 – .NET Core Tampering Vulnerability

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

7.5 · CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

EPSS

• CVE-2026-32175: 0.71% estimated exploitation activity in the next 30 days; percentile 53.62 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Executive Summary: Microsoft is releasing this security advisory to provide information about a vulnerability in .NET 8.0, .NET 9.0, and .NET 10.0. This advisory also provides guidance on what developers can do to update their applications to remove this vulnerability. A tampering vulnerability exists when .NET Core improperly handles specially crafted files. An attacker who successfully exploited this vulnerability could write arbitrary files and directories to certain locations on a vulnerable system. However, an attacker would have limited control over the destination of the files and directories. To exploit the vulnerability, an attacker must send a specially crafted file to a vulnerable system. The security update fixes the vulnerability by ensuring .NET Core properly handles files. Announcement Announcement for this issue can be found at https://github.com/dotnet/announcements/issues/396 CVSS Details - Version: 3.1 - Severity: - Score: 4.3 - Vector:…

Published by the source

18 May 2026, 19:08 UTC

Last modified by the source

15 Jul 2026, 21:49 UTC

Source last checked

26 Oct 2026, 17:05 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-rg75-q538-x34v

Preview the exact text before you copy it. Commands are read-only suggestions; review them before running anything.

# Patch Next advisory brief: CVE-2026-32175

Advisory: Microsoft Security Advisory CVE-2026-32175 – .NET Core Tampering Vulnerability
IDs: CVE-2026-32175, GHSA-rg75-q538-x34v
Record: https://patchnext.com/advisories/cve-2026-32175 (revision 1, source checked 26 Oct 2026, 17:05 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: High (CVSS 7.5)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: microsoft.netcore.app.runtime.win-x86 10.0.8, 9.0.16, 8.0.27; microsoft.netcore.app.runtime.win-arm64 10.0.8, 9.0.16, 8.0.27; microsoft.netcore.app.runtime.win-arm 10.0.8, 9.0.16, 8.0.27; microsoft.netcore.app.runtime.win-x64 10.0.8, 9.0.16, 8.0.27. A vendor fix does not mean a deployment is fixed.

## Affected components
- NuGet microsoft.netcore.app.runtime.win-x86: affected >= 8.0.0, <= 8.0.26; >= 9.0.0, <= 9.0.15; >= 10.0.0, <= 10.0.7; fixed in 9.0.16, 10.0.8, 8.0.27
- NuGet microsoft.netcore.app.runtime.win-arm64: affected >= 8.0.0, <= 8.0.26; >= 9.0.0, <= 9.0.15; >= 10.0.0, <= 10.0.7; fixed in 9.0.16, 10.0.8, 8.0.27
- NuGet microsoft.netcore.app.runtime.win-arm: affected >= 8.0.0, <= 8.0.26; >= 9.0.0, <= 9.0.15; >= 10.0.0, <= 10.0.7; fixed in 9.0.16, 10.0.8, 8.0.27
- NuGet microsoft.netcore.app.runtime.win-x64: affected >= 8.0.0, <= 8.0.26; >= 9.0.0, <= 9.0.15; >= 10.0.0, <= 10.0.7; fixed in 9.0.16, 10.0.8, 8.0.27

## Suggested inspection (read-only)
- NuGet microsoft.netcore.app.runtime.win-x86: check the installed version with your package manager.
- NuGet microsoft.netcore.app.runtime.win-arm64: check the installed version with your package manager.
- NuGet microsoft.netcore.app.runtime.win-arm: check the installed version with your package manager.
- NuGet microsoft.netcore.app.runtime.win-x64: check the installed version with your package manager.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on microsoft.netcore.app.runtime.win-x86, microsoft.netcore.app.runtime.win-arm64, microsoft.netcore.app.runtime.win-arm, microsoft.netcore.app.runtime.win-x64.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-rg75-q538-x34v (GitHub-reviewed advisory GHSA-rg75-q538-x34v lists affected ranges: NuGet microsoft.netcore.app.runtime.win-arm >=8.0.0 =9.0.0 =10.0.0 =8.0.0 =9.0.0 =10.0.0 =8.0.0 =9.0.0 =10.0.0 =8.0.0 =9.0.0 =10.0.0 <=10.0.7)

Commands are suggestions: review each one before running it.