External risk intelligence

Microsoft DirectX Kernel Privilege Escalation

CVE advisoryKnown Exploit

CVE-2018-8406

An elevation of privilege vulnerability exists in the DirectX Graphics Kernel driver, affecting certain Windows operating systems. This flaw could allow an attacker with local access to gain elevated privileges on a system. Business risk includes potential unauthorized access to sensitive data and system control.

1Halo Surface Signal

Microsoft Windows 10 1507

External exposure likelihood

Halo Surface Signal score for CVE-2018-8406

This vulnerability affects a core operating system kernel driver (DXGKRNL). Elevation of privilege vulnerabilities in local kernel drivers are inherently local-only and require an attacker to already have a presence on the system to execute, meaning there is no direct public network exposure.

Horizon Alert

Summary of the vulnerability and why it matters

The DirectX Graphics Kernel (DXGKRNL) driver in certain Windows operating systems is susceptible to a vulnerability related to memory object handling. This flaw can allow an attacker with local access to elevate their privileges on the affected system. Such an elevation of privilege could potentially lead to unauthorized access to sensitive data or the execution of malicious code, posing a risk to the integrity and confidentiality of business operations.

  • Vulnerable: DirectX Graphics Kernel (DXGKRNL) driver
  • Flaw: Improper handling of memory objects
  • Impact: Unauthorized privilege escalation

Attack Path

How an attacker could exploit the issue

This vulnerability involves the DirectX Graphics Kernel (DXGKRNL) driver improperly handling objects in memory. Attackers can exploit this to elevate their privileges on an affected system. This could lead to unauthorized access and control over the system.

  • Local access required
  • Trigger memory object handling
  • Gain elevated system control

Live Threat

Current exploitation, exposure, and threat context

This vulnerability could allow an attacker with local access to escalate their privileges on affected Windows systems. Exploitation would require an attacker to already be present on the system, meaning it is not a remote threat. The potential impact includes unauthorized access to sensitive data and system control.

  • Attacker skill level: Basic
  • Required access or conditions: Local access
  • Business risk or urgency: High

Priority actions

Operational Fix

Recommended remediation, mitigation, and detection steps

An elevation of privilege vulnerability has been identified within the DirectX Graphics Kernel (DXGKRNL) driver. This issue could allow an attacker with local access to gain elevated privileges on affected Windows systems. The vulnerability stems from improper handling of memory objects by the driver.

  • Find affected assets.
  • Reduce exposure or isolate risk.
  • Fix, verify, and monitor.

Frequently asked questions

What is the DirectX Graphics Kernel (DXGKRNL) and what is it used for?

The DirectX Graphics Kernel (DXGKRNL) is a driver within Windows operating systems. It's part of the DirectX suite, which handles graphics and multimedia tasks, including managing how applications interact with graphics hardware for games and other visually intensive software.

What type of vulnerability is CVE-2018-8406 and how does it affect systems?

CVE-2018-8406 is an elevation of privilege vulnerability, specifically a CWE-404 "Improper Resource Shutdown or Release" weakness. It means the DXGKRNL driver improperly manages memory objects, allowing a local attacker to gain higher-level permissions than they should have on the system.

How can an attacker trigger the vulnerability in CVE-2018-8406?

Exploiting this vulnerability requires an attacker to already have local access to the affected Windows system. The bug is triggered by the DXGKRNL driver's improper handling of objects in memory, which a local attacker can manipulate to escalate their privileges.

Who needs to be concerned about this CVE, considering its access type?

Organizations running affected versions of Windows 10 or Windows Server should be concerned. Since this vulnerability requires local access, it poses a risk to systems that an attacker could physically access or already has a foothold on, rather than being directly exposed to the internet.

What are the first steps for managing this vulnerability?

The initial steps involve identifying which systems are running the affected Windows versions. Once identified, focus on reducing the potential for local access exploits, isolating risky systems if possible, and applying any necessary updates or patches provided by Microsoft to fix the driver issue.

References