---
id: CVE-2026-85790
title: >-
  Use after free in Microsoft QUIC allows an unauthorized attacker to disclose
  information over a network.
summary: >-
  Use after free in Microsoft QUIC allows an unauthorized attacker to disclose
  information over a network.
severity: medium
cvss: 5.9
cvssVector: 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N'
cwe:
  - CWE-416
vendor: Microsoft
product: Microsoft.Native.Quic.MsQuic.Schannel
affected:
  - 'Microsoft.Native.Quic.MsQuic.Schannel >= 1.9.0, <= 2.6.1'
patched:
  - Microsoft.Native.Quic.MsQuic.Schannel 2.6.2
published: '2026-10-13'
updated: '2026-10-13'
sourceUpdated: '2026-10-13T21:19:19.137'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-85790'
references:
  - url: 'https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-85790'
    label: secure@microsoft.com
  - url: 'https://github.com/dotnet/runtime/security/advisories/GHSA-2mxg-prvg-9jfg'
  - url: 'https://github.com/dotnet/announcements/issues/470'
  - url: 'https://github.com/dotnet/runtime/issues/135704'
  - url: 'https://github.com/advisories/GHSA-2mxg-prvg-9jfg'
tags:
  - nvd
  - ghsa
  - nuget
aliases:
  - GHSA-2mxg-prvg-9jfg
ecosystem: nuget
ingestedAt: '2026-10-13T19:43:29.165Z'
---

## Overview

Use after free in Microsoft QUIC allows an unauthorized attacker to disclose information over a network.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.

## Package advisory (CVE-2026-85790)

Affected packages:

- `Microsoft.Native.Quic.MsQuic.Schannel >= 1.9.0, <= 2.6.1`

Patched in:

- `Microsoft.Native.Quic.MsQuic.Schannel 2.6.2`

Source: https://github.com/advisories/GHSA-2mxg-prvg-9jfg