CVE-2025-47159 Overview
CVE-2025-47159 is a local privilege escalation vulnerability in the Windows Virtualization-Based Security (VBS) Enclave. The flaw stems from a protection mechanism failure [CWE-693] that allows an authenticated local attacker to elevate privileges on affected Windows client and server systems. Microsoft published the advisory on July 8, 2025, covering supported Windows 10, Windows 11, and Windows Server releases.
Critical Impact
An authorized local attacker can bypass VBS Enclave protections to gain elevated privileges, compromising confidentiality, integrity, and availability of the host.
Affected Products
- Microsoft Windows 10 (1507, 1607, 1809, 21H2, 22H2)
- Microsoft Windows 11 (22H2, 23H2, 24H2)
- Microsoft Windows Server 2016, 2019, 2022, 2022 23H2, and 2025
Discovery Timeline
- 2025-07-08 - CVE-2025-47159 published to NVD
- 2025-07-08 - Microsoft releases security update through the Microsoft Security Response Center
- 2026-06-17 - Last updated in NVD database
Technical Details for CVE-2025-47159
Vulnerability Analysis
The vulnerability resides in Windows Virtualization-Based Security (VBS) Enclaves. VBS uses hardware virtualization to isolate a secure region of memory, referred to as Virtual Trust Level 1 (VTL1), from the normal operating system running at VTL0. Enclaves within VBS host sensitive code and secrets that the standard kernel cannot access directly.
Microsoft classifies the issue as a protection mechanism failure [CWE-693]. This category applies when a security control exists but does not enforce its intended boundary under specific conditions. In this case, the enclave protection can be circumvented by a local attacker who already holds valid credentials on the system.
Successful exploitation grants the attacker higher privileges than the account originally possessed. Because the enclave is designed to protect isolated secrets and privileged operations, bypassing it undermines a foundational Windows security boundary.
Root Cause
The root cause is a failure in the VBS Enclave to correctly enforce its trust boundary between VTL0 and the isolated VTL1 code. Microsoft has not published low-level implementation details in the public advisory.
Attack Vector
The attack vector is local and requires low privileges with no user interaction. An attacker with an authenticated foothold, such as a standard user shell or a compromised low-privilege service, can trigger the flaw to escalate to a higher-privileged context. The vulnerability is not remotely exploitable over the network. See the Microsoft CVE-2025-47159 Update for vendor-authoritative details.
Detection Methods for CVE-2025-47159
Indicators of Compromise
- Unexpected creation or loading of VBS enclave modules by non-system processes or unsigned binaries.
- Local user accounts spawning processes running as SYSTEM or with elevated integrity levels shortly after execution of unknown binaries.
- Anomalous calls into enclave APIs such as CreateEnclave, LoadEnclaveData, InitializeEnclave, or CallEnclave from user-context processes.
Detection Strategies
- Monitor Windows Event Logs for privilege assignment events (Event IDs 4672, 4673, 4674) originating from standard user sessions.
- Baseline enclave-related API usage across the environment and alert on processes outside the expected allowlist.
- Correlate patch state telemetry with authentication and process creation events to identify unpatched hosts exhibiting privilege escalation behavior.
Monitoring Recommendations
- Track installation status of the July 2025 Microsoft security updates across all Windows endpoints and servers.
- Alert on token manipulation, integrity level changes, and impersonation events by non-administrative processes.
- Ingest endpoint telemetry into a centralized data lake to enable retrospective hunts for enclave abuse patterns.
How to Mitigate CVE-2025-47159
Immediate Actions Required
- Apply the Microsoft security update referenced in the Microsoft CVE-2025-47159 Update advisory to all affected Windows 10, Windows 11, and Windows Server systems.
- Prioritize patching on multi-user systems, jump hosts, and servers where local access by lower-privileged users is possible.
- Audit local accounts and remove unnecessary interactive logon rights to reduce the pool of potential attackers.
Patch Information
Microsoft addressed CVE-2025-47159 through the security update published on July 8, 2025. Administrators should consult the Microsoft Security Response Center advisory for the specific KB article numbers that correspond to each affected Windows build and deploy them through Windows Update, WSUS, Microsoft Intune, or Configuration Manager.
Workarounds
- No official workaround has been published by Microsoft. Installing the security update is the required remediation.
- Enforce least privilege and application allowlisting to limit which binaries can execute in user context and reduce exploitation opportunity.
- Restrict local logon rights and enable credential hardening features such as Credential Guard to reduce the value of a foothold.
# Verify installation of relevant security update on Windows
Get-HotFix | Sort-Object -Property InstalledOn -Descending | Select-Object -First 20
# Check VBS and enclave status
Get-CimInstance -ClassName Win32_DeviceGuard -Namespace root\Microsoft\Windows\DeviceGuard
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
