CVE-2025-48822: Windows 10 1607 Hyper-V RCE Vulnerability

CVE-2025-48822 Overview

CVE-2025-48822 is an out-of-bounds read vulnerability in Windows Hyper-V that allows an unauthorized attacker to execute code locally. This memory corruption flaw (CWE-125) affects the Hyper-V virtualization component across multiple versions of Windows client and server operating systems. An attacker who successfully exploits this vulnerability could potentially escape the guest VM sandbox or execute arbitrary code in the context of the Hyper-V host.

Critical Impact

This vulnerability enables local code execution through an out-of-bounds read condition in Windows Hyper-V, potentially allowing guest-to-host escape scenarios in virtualized environments.

Affected Products

• Microsoft Windows 10 1607, 1809, 21H2, 22H2 (x64)
• Microsoft Windows 11 22H2, 23H2, 24H2
• Microsoft Windows Server 2016, 2019, 2022, 2022 23H2, 2025

Discovery Timeline

• July 8, 2025 - CVE-2025-48822 published to NVD
• July 15, 2025 - Last updated in NVD database

Technical Details for CVE-2025-48822

Vulnerability Analysis

This vulnerability is classified as an out-of-bounds read (CWE-125), a type of memory corruption flaw where the software reads data past the end of the intended buffer. In the context of Windows Hyper-V, this occurs within the virtualization stack, potentially allowing an attacker to read sensitive memory contents or leverage the memory corruption to achieve code execution.

The attack requires local access and user interaction, meaning an attacker would need to convince a user to perform an action such as opening a malicious file or running a crafted application within a Hyper-V guest environment. Due to the scope change indicated in the vulnerability assessment, successful exploitation could impact resources beyond the vulnerable component's security scope—specifically enabling a guest VM to affect the host system.

Root Cause

The root cause is improper bounds checking when reading data within the Hyper-V virtualization subsystem. When processing certain operations, the affected code fails to properly validate buffer boundaries before performing read operations, allowing memory access beyond the allocated buffer. This can lead to information disclosure of adjacent memory contents or, when chained with additional techniques, arbitrary code execution.

Attack Vector

The attack vector is local, requiring the attacker to have access to a Hyper-V guest virtual machine or local system access. The attacker must craft a malicious payload that triggers the out-of-bounds read condition in the Hyper-V component. Since user interaction is required, attack scenarios may include:

• Crafting a malicious file that, when processed within a guest VM, triggers the vulnerability
• Social engineering a user to execute a malicious application within the virtualized environment
• Leveraging existing access to a guest VM to attempt guest-to-host escape

The vulnerability does not require privileges to exploit, making it accessible to unprivileged users within the guest environment. Successful exploitation could compromise the confidentiality and integrity of both the guest and host systems.

Detection Methods for CVE-2025-48822

Indicators of Compromise

• Unexpected crashes or error events in the vmwp.exe (Virtual Machine Worker Process) or related Hyper-V processes
• Anomalous memory access patterns in Hyper-V components captured through Event Tracing for Windows (ETW)
• Unusual process behavior or privilege changes originating from guest VM boundaries

Detection Strategies

• Monitor Windows Event Logs for Hyper-V related errors, particularly events in the Microsoft-Windows-Hyper-V-Worker provider
• Deploy Endpoint Detection and Response (EDR) solutions such as SentinelOne to detect anomalous behavior in virtualization stack processes
• Implement behavioral analysis rules to identify potential VM escape attempts or unusual cross-boundary memory operations

Monitoring Recommendations

• Enable enhanced logging for Hyper-V components and virtualization events
• Configure alerting for unexpected terminations or exceptions in vmwp.exe, vmms.exe, and related Hyper-V services
• Utilize SentinelOne's Singularity platform to monitor for exploitation attempts targeting hypervisor components

How to Mitigate CVE-2025-48822

Immediate Actions Required

• Apply the latest Windows security updates from Microsoft immediately across all affected systems
• Prioritize patching on systems running Hyper-V workloads, especially production hypervisor hosts
• Restrict local access to Hyper-V hosts and limit the attack surface by applying least privilege principles
• Review guest VM configurations and reduce unnecessary access to host resources

Patch Information

Microsoft has released security updates addressing CVE-2025-48822 as part of their security update release cycle. Administrators should consult the Microsoft Security Response Center advisory for specific KB article numbers and patch details for each affected Windows version. Apply updates through Windows Update, WSUS, or your enterprise patch management solution.

Workarounds

• If patching cannot be performed immediately, consider temporarily disabling Hyper-V on non-critical systems until updates can be applied
• Implement network segmentation to isolate Hyper-V hosts from untrusted networks
• Restrict which users can create or interact with virtual machines through Hyper-V Manager permissions
• Monitor affected systems closely with enhanced logging until patches are deployed

# Temporarily disable Hyper-V role (requires reboot)
Disable-WindowsOptionalFeature -Online -FeatureName Microsoft-Hyper-V-All

# Check current Hyper-V status
Get-WindowsOptionalFeature -Online -FeatureName Microsoft-Hyper-V

# Re-enable Hyper-V after patching
Enable-WindowsOptionalFeature -Online -FeatureName Microsoft-Hyper-V-All