External risk intelligence

Windows CLFS Driver Elevation of Privilege Vulnerability.

CVE advisoryKnown Exploit

CVE-2024-49138

A vulnerability in the Windows Common Log File System Driver allows an attacker with local access to escalate privileges. This could impact system integrity and data confidentiality, posing a significant business risk. Prompt application of vendor updates is recommended.

1Halo Surface Signal

Microsoft Windows 10 1507

before 10.0.10240.20857before 10.0.14393.7606before 10.0.17763.6659before 10.0.19044.5247before 10.0.19045.5247before 10.0.22621.4602before 10.0.22631.4602before 10.0.26100.2605r2;...

External exposure likelihood

Halo Surface Signal score for CVE-2024-49138

This vulnerability affects the Windows Common Log File System (CLFS) driver, which is a local kernel-level component. Exploitation requires an attacker to already have local access to the system to execute code. It is not reachable over a network, and there is no public-facing attack surface for this component in standard deployments.

Horizon Alert

Summary of the vulnerability and why it matters

A vulnerability in the Windows Common Log File System Driver can allow an attacker to gain elevated privileges on a system. This flaw resides within a core component of the Windows operating system responsible for managing log files. Exploiting this weakness could permit an unauthorized user with existing local access to execute code with higher permissions, potentially impacting system integrity and data confidentiality.

Windows Common Log File System Driver
Flaw allows privilege escalation
Unauthorized access, data compromise

Attack Path

How an attacker could exploit the issue

This vulnerability in the Windows Common Log File System Driver allows for an elevation of privilege. An attacker with local access to a system can exploit this flaw to gain higher-level permissions. The attack involves triggering a specific condition within the driver, which then leads to the attacker gaining control. This could impact the confidentiality, integrity, and availability of the affected system.

Requires local system access.
Attacker triggers a driver condition.
Attacker gains elevated control.

Live Threat

Current exploitation, exposure, and threat context

A vulnerability within the Windows Common Log File System Driver could allow an attacker with local access to escalate their privileges. This means an individual already on a system could gain higher-level control, potentially impacting data integrity and system operations. The potential for privilege escalation presents a significant business risk.

Likely attacker skill level: Low
Required access or conditions: Local system access
Business risk or urgency: High

Priority actions

Operational Fix

Recommended remediation, mitigation, and detection steps

This vulnerability in the Windows Common Log File System Driver could allow an attacker with local access to elevate their privileges. This could impact the integrity and confidentiality of systems and data, posing a significant business risk. The immediate focus should be on identifying and protecting affected assets.

Find all Windows systems.
Isolate affected systems if possible.
Apply vendor updates and verify.
Monitor for related activity.

Frequently asked questions

What is the Windows Common Log File System Driver and its role in system security?

The Windows Common Log File System (CLFS) Driver is a foundational component of the Windows operating system responsible for managing log files efficiently. It provides a robust, low-level service that various Windows components and applications utilize for recording critical events and data, ensuring system stability and aiding in diagnostics.

What type of vulnerability is CVE-2024-49138 and how does it compromise Windows systems?

CVE-2024-49138 is a privilege escalation vulnerability, specifically a heap-based buffer overflow (CWE-122). It enables an attacker with existing local access to a Windows system to exploit a flaw in the CLFS driver. This exploitation allows them to gain administrator-level permissions, significantly increasing their control over the system.

How can an attacker exploit the Windows CLFS Driver vulnerability, and what is the scope of impact?

Exploitation of CVE-2024-49138 requires an attacker to have local system access. By triggering a specific condition within the CLFS driver, the attacker can achieve a heap-based buffer overflow. This attack vector allows them to escalate their privileges, potentially leading to unauthorized access, modification, or deletion of data and impacting system confidentiality, integrity, and availability.

What is the significance of CVE-2024-49138's local attack vector and its relevance to system security?

The fact that CVE-2024-49138 requires local system access is a key aspect of its relevance. While not directly exploitable over a network, it poses a significant risk if an attacker gains initial access through other means. This local privilege escalation capability can allow an attacker to deepen their foothold and execute more damaging actions on an already compromised system.

What are the recommended practical steps to address the Windows CLFS Driver privilege escalation vulnerability?

To mitigate CVE-2024-49138, it is crucial to identify all Windows systems within your environment. If possible, isolate systems confirmed to be affected. The primary remediation involves applying the latest vendor-provided security updates and verifying their successful implementation. Continuous monitoring for any suspicious activity related to privilege escalation is also recommended.

References

Written by Nicholas Merritt

External-surface CVE analysis and Halo Surface Signal prioritization for Halo Threat Intelligence.