CVE-2026-35247: Oracle VM VirtualBox Privilege Escalation

CVE-2026-35247 Overview

CVE-2026-35247 is an improper access control vulnerability affecting the Core component of Oracle VM VirtualBox. This flaw allows a high-privileged attacker with local access to the infrastructure where Oracle VM VirtualBox executes to compromise the application and potentially impact additional products beyond VirtualBox itself due to scope change.

The vulnerability is classified under CWE-284 (Improper Access Control), indicating that the software does not properly restrict access to resources or functionality. While the attack requires high privileges and local access, successful exploitation can result in unauthorized access to critical data or complete access to all Oracle VM VirtualBox accessible data.

Critical Impact

Successful exploitation enables attackers with high privileges to access critical data across Oracle VM VirtualBox and potentially impact additional virtualized products due to scope change.

Affected Products

• Oracle VM VirtualBox version 7.2.6
• Oracle Virtualization Core component
• Systems running affected VirtualBox versions with local attacker access

Discovery Timeline

• April 21, 2026 - CVE-2026-35247 published to NVD
• April 23, 2026 - Last updated in NVD database

Technical Details for CVE-2026-35247

Vulnerability Analysis

This vulnerability exists within the Core component of Oracle VM VirtualBox and is characterized by improper access control mechanisms. The flaw is considered easily exploitable, though it requires the attacker to already possess high privileges on the local infrastructure where VirtualBox is running.

What makes this vulnerability particularly noteworthy is the scope change characteristic—while the vulnerability exists in Oracle VM VirtualBox, successful attacks may significantly impact additional products. This suggests that an attacker exploiting this flaw could potentially escape the VirtualBox environment or access data from other virtualized guests, violating the isolation boundaries that virtualization is designed to provide.

The confidentiality impact is high, meaning attackers can gain access to critical data or all VirtualBox-accessible data. However, no integrity or availability impacts are associated with this vulnerability, indicating that while data can be read, it cannot be modified or destroyed through this attack vector.

Root Cause

The root cause of CVE-2026-35247 is improper access control (CWE-284) within the VirtualBox Core component. The vulnerability stems from insufficient restrictions on access to resources or functionality, allowing privileged local users to access data they should not be authorized to view. The specific implementation flaw enables unauthorized data access that can extend beyond the immediate VirtualBox environment.

Attack Vector

Exploitation requires local access to the system where Oracle VM VirtualBox is installed, combined with high privileges on that infrastructure. The attack complexity is low, meaning once the prerequisites are met, exploitation is straightforward and does not require user interaction.

An attacker would need to:

1. Gain local access to a system running Oracle VM VirtualBox 7.2.6
2. Possess high-level privileges on the infrastructure
3. Interact with the VirtualBox Core component to trigger the improper access control condition
4. Access confidential data from VirtualBox or potentially from other products affected by the scope change

The attack does not require network access or user interaction, making it a concern for environments where local privileged access is possible, such as shared virtualization hosts or systems with multiple administrative users.

Detection Methods for CVE-2026-35247

Indicators of Compromise

• Unexpected access patterns to VirtualBox configuration files and virtual machine data stores
• Anomalous read operations on virtual disk images (.vdi, .vmdk, .vhd files) from privileged processes
• Unusual process behavior from VBoxSVC.exe or VBoxHeadless processes accessing guest VM data
• Privileged accounts accessing VirtualBox resources outside of normal operational patterns

Detection Strategies

• Monitor for privileged users accessing VirtualBox components or data files outside normal administrative activities
• Implement file integrity monitoring on VirtualBox installation directories and virtual machine storage locations
• Enable verbose logging for VirtualBox operations and correlate with user activity logs
• Deploy endpoint detection and response (EDR) solutions to monitor for anomalous VirtualBox process behavior

Monitoring Recommendations

• Configure audit policies to log access attempts to VirtualBox directories and configuration files
• Establish baselines for normal VirtualBox administrative operations and alert on deviations
• Monitor for unauthorized access to virtual machine guest data from the host system
• Implement privileged access management (PAM) solutions to track and control high-privilege account activities

How to Mitigate CVE-2026-35247

Immediate Actions Required

• Upgrade Oracle VM VirtualBox to a patched version as specified in the Oracle Critical Patch Update April 2026
• Review and restrict high-privilege access to systems running VirtualBox to only essential personnel
• Audit all privileged accounts with access to VirtualBox infrastructure
• Implement the principle of least privilege for administrative access to virtualization hosts

Patch Information

Oracle has addressed this vulnerability in the Oracle Critical Patch Update April 2026. Organizations should review the advisory and apply the recommended patches to Oracle VM VirtualBox. The patch addresses the improper access control issue in the Core component.

Organizations running VirtualBox version 7.2.6 should prioritize applying the security update. Consult the Oracle security advisory for specific patch download links and installation instructions.

Workarounds

• Restrict local access to systems running VirtualBox to only trusted, essential personnel until patching is complete
• Implement network segmentation to isolate VirtualBox hosts from untrusted network segments
• Enable additional logging and monitoring on VirtualBox hosts to detect potential exploitation attempts
• Consider temporarily disabling VirtualBox on critical systems if patching cannot be immediately performed and the risk is deemed unacceptable

# Configuration example: Restrict access to VirtualBox directories on Linux
# Set restrictive permissions on VirtualBox configuration directory
sudo chmod 700 /etc/vbox
sudo chown root:root /etc/vbox

# Restrict access to virtual machine storage
sudo chmod 750 /path/to/vm/storage
sudo chgrp vboxusers /path/to/vm/storage

# Audit access to VirtualBox binaries
sudo auditctl -w /usr/lib/virtualbox -p rwxa -k vbox_access