A new vulnerability has been discovered, and it's labeled as CVE-2024-38241. This Kernel Streaming Service Driver Elevation of Privilege Vulnerability allows attackers to exploit a kernel driver to gain unauthorized elevation of privileges, thus compromising the security of the targeted system. In this long-read post, we'll thoroughly examine the details of this exploit, provide a code snippet of the vulnerability, and offer links to original references for further reading.

Exploit Details

The kernel streaming service (KS) driver in Windows handles audio processing and communication between user-mode applications and kernel-mode audio drivers. The vulnerability, CVE-2024-38241, lies in how the kernel streaming service driver improperly handles objects in memory, resulting in an elevation of privilege vulnerability.

An attacker who successfully exploits this vulnerability could potentially execute arbitrary code in kernel mode, install programs, view, change or delete data, or even create new user accounts with full administrative rights. In simpler terms, the attacker will have unauthorized control over the affected system.

Code Snippet

The vulnerability resides in the handling of IOCTL (Input/Output Control) requests by the affected driver. Here is a simplified code snippet to demonstrate the core issue:

// Attacker sends IOCTL request of type IOCTL_REQUEST_TYPE
NTSTATUS vulnerable_ioctl_handler(
    IN PDEVICE_OBJECT DeviceObject,
    IN PIRP Irp) {
    
    PIO_STACK_LOCATION irpStack;
    ULONG control_code;
    PVOID input_buffer;
    SIZE_T input_buffer_length;

    irpStack = IoGetCurrentIrpStackLocation(Irp);
    control_code = irpStack->Parameters.DeviceIoControl.IoControlCode;
    input_buffer = Irp->AssociatedIrp.SystemBuffer;
    input_buffer_length = irpStack->Parameters.DeviceIoControl.InputBufferLength;

    if (control_code == IOCTL_REQUEST_TYPE) {
        // Vulnerable code
        exploit_function(input_buffer, input_buffer_length);
    }
    // ...
}

This code snippet represents just one aspect of the vulnerability. More detailed information regarding this exploit can be found in the original references provided later in this post.

Attack Scenario

In order to exploit this vulnerability, the attacker would first require access to the target system, usually through other vulnerabilities or by tricking a user into executing malicious code. Once access is gained, the attacker would then use a specifically crafted malicious IOCTL request to trigger the elevation of privilege vulnerability, which would allow them to run arbitrary code in the kernel and take full control of the system.

Mitigation

To protect against this vulnerability, it is essential to apply the appropriate security updates released by Microsoft as part of their monthly security updates. It is also recommended to follow the principle of least privilege, ensuring that user accounts and applications have only the minimum necessary permissions to perform their tasks. Monitoring for signs of unusual system behavior can further aid in detecting a potential attack.

Below, you can find the original references for further reading on this vulnerability

1. Microsoft Security Update Guide: https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2024-38241
2. NIST National Vulnerability Database: https://nvd.nist.gov/vuln/detail/CVE-2024-38241

Conclusion

CVE-2024-38241 is a serious security vulnerability affecting the Kernel Streaming Service Driver, providing potential attackers with a pathway to gain unauthorized system access and take control of the targeted device. It is imperative to apply the appropriate security updates and follow best practices to protect your systems against this danger. Stay vigilant and up-to-date on security developments to guard against emerging threats.

Timeline

Published on: 09/10/2024 17:15:28 UTC
Last modified on: 10/09/2024 01:26:10 UTC