Vulnerability in Microsoft.Native.Quic.MsQuic.Schannel (CVE-2026-105016)
Summary
Vulnerability in Microsoft.Native.Quic.MsQuic.Schannel (CVE-2026-105016). Successful exploitation can lead to full system takeover. Exploitable via Microsoft.Native.Quic.MsQuic.Schannel. Mitigation: upgrade to 2.5.11-ci.159417053 or later.
Original description
The description as published by the source.
Executive summary
Microsoft is releasing this security advisory to provide information about a vulnerability in Microsoft QUIC as used by .NET 8.0, .NET 9.0, .NET 10.0, and .NET 11 RC2 on Windows. This advisory also provides guidance on what developers can do to update their applications to remove this vulnerability.
A crafted IPv6 QUIC packet can reach the Microsoft QUIC HTTP/3 path without authentication or user interaction and trigger remote code execution.
Announcement
Announcement for this issue can be found at https://github.com/dotnet/announcements/issues/446
CVSS Details
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Version: 3.1
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Severity: Critical
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Score: 9.8
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Vector:
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H -
Weakness: CWE-122 (Heap-based Buffer Overflow)
Affected Platforms
- Platforms: Windows
- 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.Native.Quic.MsQuic.Schannel | >= 2.5.11-ci.156755675, <= 2.5.11-ci.156755675 | 2.5.11-ci.159417053 |
Advisory FAQ
How do I know if I am affected?
If your application uses a package version listed in affected packages, it is exposed to the vulnerability.
How do I fix the issue?
- Install the latest servici…
Source: GitHub Security Advisories (Global) NVD GitHub Advisory
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2026-105016 has been found in Microsoft.Native.Quic.MsQuic.Schannel.
Attackers can target a specific entry point like Microsoft.Native.Quic.MsQuic.Schannel over the network to misuse the product.
Successful exploitation can lead to full system takeover. CVSS score: 9.8/10.
What to do: upgrade Microsoft.Native.Quic.MsQuic.Schannel to 2.5.11-ci.159417053 or later.
If unsure, ask your IT team or search "Microsoft.Native.Quic.MsQuic.Schannel CVE-2026-105016" on the vendor's site.
CVE-2026-105016 (Microsoft.Native.Quic.MsQuic.Schannel) — CWE-122 / CVSS v3 9.8
Attack vector: remote (network-reachable) / unauthenticated / no user interaction
Attack surface: Microsoft.Native.Quic.MsQuic.Schannel
Patched: 2.5.11-ci.159417053 — apply immediately
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
A vulnerability (CWE-122) exists in Microsoft.Native.Quic.MsQuic.Schannel. Attackers reach the vulnerable code path via Microsoft.Native.Quic.MsQuic.Schannel without authentication.
Check the vendor advisory for the affected versions of Microsoft.Native.Quic.MsQuic.Schannel. Attack surface: Microsoft.Native.Quic.MsQuic.Schannel.
Severity: Critical (CVSS 9.8/10). Successful exploitation can lead to full system takeover.
Update to 2.5.11-ci.159417053.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run grep -r 'Microsoft.Native.Quic.MsQuic.Schannel' . against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
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1Identify exposure identify
grep -r 'Microsoft.Native.Quic.MsQuic.Schannel' . | grep -v node_modulesリポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で
Microsoft.Native.Quic.MsQuic.Schannelを grep し、稼働しているサービス・バージョンを把握する。 -
2Apply patch patch
Upgrade Microsoft.Native.Quic.MsQuic.Schannel to 2.5.11-ci.159417053ステージング環境で 2.5.11-ci.159417053 に上げて回帰テスト → 本番反映。回帰テストはアプリの主要ハッピーパスを含めること。
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3Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
Affected packages
References
- web github.com
- web github.com
- web github.com
- web github.com
- web secure@microsoft.com