CVE-2008-3431: VirtualBox VBoxDrv.sys IOCTL buffer validation privilege escalation

Automated analysis

Generated by VULONE's analysis model from the NVD record, CISA KEV and EPSS data on 17 September 2026. Confidence: high.

high priorityThe flaw is a local privilege escalation with public exploit code and KEV listing, but it requires an existing low-privileged local account and affects an old VirtualBox release.

What it is

VBoxDrvNtDeviceControl in VBoxDrv.sys in Sun xVM VirtualBox before 1.6.4 uses the METHOD_NEITHER IOCTL communication method and fails to validate the buffer associated with the Irp object. A local user can open the \\.\VBoxDrv device and send a crafted kernel address via DeviceIoControl to escalate privileges. The flaw matters because it lets an unprivileged local account reach kernel-level code execution on affected hosts.

Impact

An attacker with local access gains elevated privileges, up to kernel-level execution, on the host running the vulnerable VirtualBox driver. That access can be used to disable protections, tamper with other workloads, or move further into the host.

Attack surface

Reached locally by opening the \\.\VBoxDrv device and issuing a DeviceIoControl call with a crafted kernel address; no user interaction is required. The CVSS vector (AV:L/PR:L/UI:N) indicates the attacker must already hold a low-privileged local account on the machine.

Exploitation

CVE-2008-3431 is listed in CISA KEV (added 2022-03-03), and multiple references carry an Exploit tag, including Exploit-DB 6218 and a Core Security advisory. EPSS 30-day probability is about 6.9 percent (93.8th percentile), so exploitation is documented and public.

What to do

• Upgrade VirtualBox to 1.6.4 or later, or to a currently supported release, per the vendor changelog.
• If the VBoxDrv driver is not needed, remove or disable the VirtualBox host driver on systems where it is not required.
• Restrict local interactive and service accounts on hosts running VirtualBox so untrusted users cannot open the \\.\VBoxDrv device.
• Monitor vendor advisories and apply the CISA KEV required action (apply updates per vendor instructions) within the due date.
• Where feasible, isolate VirtualBox host workloads so a local privilege escalation does not expose other sensitive systems.

Detection

• Alert on processes opening the \\.\VBoxDrv device or issuing DeviceIoControl calls to it from unexpected or non-VirtualBox processes.
• Monitor for driver load events involving VBoxDrv.sys and correlate with unusual parent processes or user contexts.
• Watch for local privilege escalation indicators such as unexpected token elevation, new admin group membership, or SYSTEM-level child processes spawned from user sessions.
• Audit hosts for VirtualBox versions below 1.6.4 and track remediation status against the KEV due date.

This assessment is produced automatically and is not human-reviewed. Verify against the vendor advisory before acting on it.