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Windows Deployment Services Hands-Free Deployment RCE

IdentifiersCVE-2026-0386CWE-284· Improper Access Control

CVE-2026-0386 is a critical remote code execution vulnerability in Windows Deployment Services (WDS), specifically in the Hands-Free Deployment functionality. The issue stems from improper access control in the handling of Unattend.xml answer files, which are transmitted over an unauthenticated RPC channel and exposed via the RemoteInstall share in native WDS deployment scenarios. Because these files can contain sensitive deployment configuration data, including credentials, an unauthenticated attacker on an adjacent network can intercept the file during network-based OS deployment and use the exposed information or inject malicious content that executes during the deployment process. Microsoft states the issue affects Windows Server versions from Server 2008 through Server 2025, including Server 2016, 2019, 2022, and version 23H2.

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ANALYST BRIEF

Impact, mitigation & remediation

What it means. What to do now. Patch path, mitigations, and the assume-compromise checklist.

Impact

What an attacker gets, and what they’ve been doing with it.

Successful exploitation can allow an unauthenticated attacker on the same or adjacent network to obtain sensitive data from Unattend.xml files, including embedded credentials, and achieve remote code execution during OS deployment. Reported consequences include compromise of deployment workflows, poisoning of deployed images, SYSTEM-level code execution on deployed systems, credential theft, and potential lateral movement within an enterprise domain. The vulnerability has high confidentiality, integrity, and availability impact.

Mitigation

If you can’t patch tonight, do this now.

Disable WDS Hands-Free Deployment by setting HKLM\SYSTEM\CurrentControlSet\Services\WdsServer\Providers\WdsImgSrv\Unattend\AllowHandsFreeFunctionality to 0 after installing the relevant updates. Review all WDS configurations for Unattend.xml usage, monitor the Microsoft-Windows-Deployment-Services-Diagnostics/Debug event log for warnings or errors about insecure unattend requests or insecure configuration, and avoid re-enabling the feature. Although AllowHandsFreeFunctionality can be set to 1 in Phase 2 to restore behavior, Microsoft explicitly warns that this is not a secure configuration and should only be used as a short-term bridge if unavoidable.

Remediation

Patch, then assume compromise.

Apply the Windows security updates released on or after 2026-01-13 that introduce the WDS hardening changes for CVE-2026-0386, and adopt Microsoft's phased deprecation of Hands-Free Deployment. Microsoft has disabled the feature by default beginning with the April 2026 phase, and states that Hands-Free Deployment is no longer a supported feature. Organizations should migrate away from this WDS capability and use alternative deployment methods such as Microsoft Intune, Windows Autopilot, or Microsoft Configuration Manager where appropriate.
PUBLIC EXPLOITS

Exploits

No valid public exploits. Mallory filtered out 1 candidate as fakes, detection scripts, or README-only repos.

VALID 0 / 1 TOTALView more in app

All candidate exploits were filtered out by Mallory's validation.

EXPOSURE SURFACE

Affected products & vendors

Products and vendors Mallory has correlated with this vulnerability. Open in Mallory to drill down to specific CPE configurations and version ranges.

VendorProductType
Microsoft CorporationWindows Server 2008operating_system
Microsoft CorporationWindows Server 2008 R2operating_system
Microsoft CorporationWindows Server 2008 Sp2operating_system
Microsoft CorporationWindows Server 2012operating_system
Microsoft CorporationWindows Server 2012 R2operating_system
Microsoft CorporationWindows Server 2016operating_system
Microsoft CorporationWindows Server 2019operating_system
Microsoft CorporationWindows Server 2022operating_system
Microsoft CorporationWindows Server 2022 23h2operating_system
Microsoft CorporationWindows Server 2025operating_system
Microsoft CorporationWindows Server 23h2operating_system

Vendor-confirmed product mapping. Mallory continuously reconciles this list against your asset inventory.

What this page doesn’t show

The version that knows your environment.

This page is what’s public. Mallory adds the parts that aren’t: which of your assets are affected, which adversaries are exploiting it right now, which detections to deploy, and what to do tonight.
Exposure mapping

Query your assets running an affected version, and investigate the blast radius.

Threat actor evidence

Every observed campaign linking this CVE to a named adversary.

Associated malware

Malware families riding this exploit, with evidence and IOCs.

Detection signatures

YARA, Sigma, Snort, and vendor rules, auto-deployed to your SIEM.

Vendor-by-vendor mapping

Cross-references every affected SKU, including bundled OEM variants.

Social activity14

Community discussion across Reddit, Mastodon, and other social sources.