CVE-2024-55408: ASUS AsusSAIO.sys Driver Privilege Escalation

CVE-2024-55408 Overview

CVE-2024-55408 is an improper access control vulnerability in the ASUS AsusSAIO.sys kernel driver. The driver fails to properly restrict access to sensitive I/O Control (IOCTL) handlers. A local attacker who supplies crafted IOCTL requests can misuse driver functionality exposed through this interface. The weakness maps to CWE-862: Missing Authorization.

Critical Impact
Local users can invoke privileged driver operations exposed by AsusSAIO.sys, enabling misuse of low-level system functionality provided by the ASUS System Analysis I/O driver.

Affected Products

ASUS AsusSAIO.sys driver
ASUS System Control Interface components bundled with MyASUS
Windows systems where the vulnerable driver is loaded

Discovery Timeline

2025-01-06 - CVE-2024-55408 published to NVD
2026-06-17 - Last updated in NVD database

Technical Details for CVE-2024-55408

Vulnerability Analysis

The AsusSAIO.sys driver exposes a device object that user-mode processes can open and interact with through DeviceIoControl calls. The driver does not enforce adequate access checks on the IOCTL handlers it registers. A local process can send crafted IOCTL requests and invoke driver functionality that should be restricted.

Because kernel drivers execute in Ring 0, any exposed capability, such as arbitrary physical memory access, MSR reads and writes, or port I/O, becomes a primitive attackers can chain. The vulnerability aligns with the broader class of Bring Your Own Vulnerable Driver (BYOVD) issues, where signed OEM drivers grant unauthorized low-level access to callers.

Root Cause

The root cause is missing authorization on the driver's IOCTL dispatch routine. The driver accepts requests from any caller that can open its device object rather than validating the caller's privilege level or restricting access through a properly configured security descriptor. This corresponds to CWE-862.

Attack Vector

Exploitation requires local access to a system where the vulnerable driver is loaded. An attacker running code on the host opens a handle to the driver's device and issues IOCTL requests that the driver processes without proper access control. The attack does not require user interaction beyond executing the attacker-supplied binary. Refer to the public technical write-up on GitHub for the affected IOCTL codes and handler behavior.

Detection Methods for CVE-2024-55408

Indicators of Compromise

Presence of AsusSAIO.sys on systems where ASUS System Analysis tooling is not required.
Unexpected process handles opened against the AsusSAIO device object by non-ASUS processes.
Newly installed instances of the driver dropped by non-standard installers, which may indicate BYOVD abuse.

Detection Strategies

Hunt for CreateFile operations targeting the AsusSAIO device name followed by DeviceIoControl calls from unsigned or untrusted binaries.
Correlate driver load events (Windows Event ID 6 in Sysmon) for AsusSAIO.sys against expected ASUS software inventory.
Alert on service creation or driver installation events that register AsusSAIO.sys outside of documented ASUS installer paths.

Monitoring Recommendations

Enable Microsoft's vulnerable driver blocklist and monitor for blocked-load telemetry referencing AsusSAIO.sys.
Collect and retain kernel driver load events in a centralized logging pipeline for historical hunting.
Track privilege escalation attempts and unusual kernel-mode activity on endpoints that have the driver installed.

How to Mitigate CVE-2024-55408

Immediate Actions Required

Inventory endpoints for the presence of AsusSAIO.sys and identify systems where the driver is not required.
Uninstall or update ASUS System Control Interface and MyASUS components through the ASUS MyASUS Support Portal.
Enable the Microsoft Vulnerable Driver Blocklist through Windows Security or Windows Defender Application Control.

Patch Information

ASUS distributes updated System Control Interface and MyASUS packages through the ASUS MyASUS Support Portal. Administrators should apply the vendor's current release, which supersedes the vulnerable AsusSAIO.sys build, and confirm the replacement driver version after installation.

Workarounds

Remove the AsusSAIO.sys driver from systems that do not require ASUS diagnostic functionality.
Apply Windows Defender Application Control (WDAC) policies that block loading of the affected driver hash.
Restrict local administrator rights to reduce the population of users able to install or interact with the driver.

bash

# Query for the driver's presence and remove the service on Windows
sc.exe query AsusSAIO
sc.exe stop AsusSAIO
sc.exe delete AsusSAIO

# Enable Microsoft Vulnerable Driver Blocklist (Windows 11 / Server 2022+)
# Settings > Windows Security > Device security > Core isolation > Microsoft Vulnerable Driver Blocklist: On