Vulnerability in Microsoft Windows (CVE-2026-44470)
Summary
Vulnerability in Microsoft Windows (CVE-2026-44470). Successful exploitation can lead to full system takeover. Mitigation: upgrade to 1.3834.0 or later.
Original description
The description as published by the source.
The Claude Desktop app gives you Claude Code with a graphical interface built for running multiple sessions side by side. Prior to 1.3834.0, the CoworkVMService component in Claude Desktop for Windows ran as SYSTEM and did not validate whether the VM bundle directory was a real directory or an NTFS directory junction before creating files within it. A local non-elevated user could replace the user-writable VM bundle directory with a directory junction pointing to an attacker-chosen location, causing the service to create a SYSTEM-owned file in an arbitrary directory. This could be leveraged for local privilege escalation. This vulnerability is fixed in 1.3834.0.
Source: NIST National Vulnerability Database NVD
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-2026-44470 has been found in Microsoft Windows.
Successful exploitation can lead to full system takeover. CVSS score: 7.8/10.
What to do: upgrade Microsoft Windows to 1.3834.0 or later.
If unsure, ask your IT team or search "Microsoft Windows CVE-2026-44470" on the vendor's site.
CVE-2026-44470 (Microsoft Windows) — CWE-59 / CVSS v3 7.8
Attack vector: local / no user interaction
Patched: 1.3834.0 — 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-59) exists in Microsoft Windows.
Check the vendor advisory for the affected versions of Microsoft Windows.
Severity: High (CVSS 7.8/10). Successful exploitation can lead to full system takeover.
Update to 1.3834.0.
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 'Windows' . 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 'Windows' . | 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
Windows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 Windows to 1.3834.0ステージング環境で 1.3834.0 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。