Sign in Sign up
JA · EN · FR
SecPulse
Categories
CVE-2026-70197 high CVSS 8.1

Out-of-Bounds Write in Microsoft.NETCore.App.Runtime.win-arm64 (CVE-2026-70197)

Summary

Out-of-bounds write in Microsoft.NETCore.App.Runtime.win-arm64 (CVE-2026-70197). Successful exploitation can lead to full system takeover. Exploitable via SocketAsyncEventArgs. Mitigation: upgrade to 10.0.13 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 System.Net.Sockets. This advisory also provides guidance on what developers can do to update their applications to remove this vulnerability.

On Windows, reusing a SocketAsyncEventArgs instance across IPv4 and IPv6 datagram sockets can retain an undersized cached native address buffer, allowing an unauthenticated out-of-bounds write during ReceiveFromAsync.

Announcement

Announcement for this issue can be found at https://github.com/dotnet/announcements/issues/466

CVSS Details

  • Version: 3.1

  • Severity: High

  • Score: 8.1

  • Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

  • Weakness: CWE-787 (Out-of-bounds Write)

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.NETCore.App.Runtime.win-arm >= 8.0.0, <= 8.0.31 8.0.32
Microsoft.NETCore.App.Runtime.win-arm64 >= 8.0.0, <= 8.0.31 8.0.32
Microsoft.NETCore.App.Runtime.win-x64 >= 8.0.0, <= 8.0.31 8.0.3…

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-2026-70197 has been found in Microsoft.NETCore.App.Runtime.win-arm64.
Attackers can target a specific entry point like SocketAsyncEventArgs over the network to misuse the product.
Successful exploitation can lead to full system takeover. CVSS score: 8.1/10.
What to do: upgrade Microsoft.NETCore.App.Runtime.win-arm64 to 10.0.13 or later.
If unsure, ask your IT team or search "Microsoft.NETCore.App.Runtime.win-arm64 CVE-2026-70197" on the vendor's site.

CVE-2026-70197 (Microsoft.NETCore.App.Runtime.win-arm64) — CWE-787 / CVSS v3 8.1
Attack vector: remote (network-reachable) / unauthenticated / no user interaction
Attack surface: SocketAsyncEventArgs / ReceiveFromAsync
Patched: 10.0.13 — 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.

❓ What is the problem

Out-of-bounds write (CWE-787) exists in Microsoft.NETCore.App.Runtime.win-arm64. Attackers reach the vulnerable code path via SocketAsyncEventArgs without authentication.

📍 Affected scope

Check the vendor advisory for the affected versions of Microsoft.NETCore.App.Runtime.win-arm64. Attack surface: SocketAsyncEventArgs / ReceiveFromAsync.

🔥 Severity

Severity: High (CVSS 8.1/10). Successful exploitation can lead to full system takeover.

🔧 How to fix

Update to 10.0.13.

🛡️ Workaround

Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.

🔍 Detection

Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run grep -r 'Microsoft.NETCore.App.Runtime.win-arm64' . 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

  1. 1
    Identify exposure identify 
    grep -r 'Microsoft.NETCore.App.Runtime.win-arm64' . | 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.NETCore.App.Runtime.win-arm64 を grep し、稼働しているサービス・バージョンを把握する。

  2. 2
    Apply patch patch 
    Upgrade Microsoft.NETCore.App.Runtime.win-arm64 to 10.0.13

    ステージング環境で 10.0.13 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。

  3. 3
    Post-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

nuget Microsoft.NETCore.App.Runtime.win-arm64
[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"10.0.13"}]}]
nuget Microsoft.NETCore.App.Runtime.win-x64
[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"10.0.13"}]}]
nuget Microsoft.NETCore.App.Runtime.win-x86
[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"10.0.13"}]}]

References

We use cookies for analytics and ad measurement. This setting applies to all Game co., Ltd. sites. Details