CVE-2024-38054: Windows 10 1507 Privilege Escalation Flaw

CVE-2024-38054 Overview

CVE-2024-38054 is an Elevation of Privilege vulnerability affecting the Kernel Streaming WOW Thunk Service Driver in Microsoft Windows. This driver is responsible for handling multimedia streaming operations and WOW64 (Windows 32-bit on Windows 64-bit) thunk services. The vulnerability allows a local attacker with low privileges to elevate their permissions to SYSTEM level, potentially gaining complete control over the affected system.

The vulnerability is classified under CWE-122 (Heap-based Buffer Overflow) and CWE-787 (Out-of-bounds Write), indicating that the flaw involves improper memory handling within the kernel driver that can be exploited to corrupt memory and execute arbitrary code with elevated privileges.

Critical Impact

A local attacker can exploit this heap-based buffer overflow vulnerability in the Kernel Streaming WOW Thunk Service Driver to escalate privileges from a low-privileged user to SYSTEM, enabling complete system compromise.

Affected Products

• Microsoft Windows 10 (versions 1507, 1607, 1809, 21H2, 22H2)
• Microsoft Windows 11 (versions 21H2, 22H2, 23H2)
• Microsoft Windows Server 2008, 2008 R2, 2012, 2012 R2, 2016, 2019, 2022, 2022 23H2

Discovery Timeline

• July 9, 2024 - CVE-2024-38054 published to NVD
• November 21, 2024 - Last updated in NVD database

Technical Details for CVE-2024-38054

Vulnerability Analysis

This vulnerability resides in the Kernel Streaming WOW Thunk Service Driver, which provides compatibility services for 32-bit applications running on 64-bit Windows systems. The driver handles multimedia streaming operations and facilitates communication between user-mode applications and kernel-mode streaming components.

The root cause involves a heap-based buffer overflow condition where input data is not properly validated before being written to a kernel memory buffer. When a specially crafted request is processed by the vulnerable driver, it can write data beyond the allocated buffer boundaries, corrupting adjacent heap metadata or memory structures.

Successful exploitation requires local access to the target system with low-level privileges. The attacker does not require any user interaction to trigger the vulnerability. The impact is significant as it affects confidentiality, integrity, and availability—all rated as high impact. An attacker who successfully exploits this vulnerability can execute arbitrary code in kernel mode with SYSTEM privileges.

Root Cause

The vulnerability stems from improper bounds checking in the Kernel Streaming WOW Thunk Service Driver when processing thunk service requests. The driver fails to properly validate the size of user-supplied data before copying it into a kernel heap buffer, resulting in a heap-based buffer overflow (CWE-122) and out-of-bounds write (CWE-787) condition.

When a malicious application sends a crafted IOCTL request to the driver with oversized or malformed data, the driver writes beyond the allocated buffer space. This memory corruption can be leveraged to overwrite critical kernel structures, function pointers, or security tokens, ultimately allowing code execution with elevated privileges.

Attack Vector

The attack vector is local, requiring the attacker to have execution capabilities on the target system. The attack follows these general stages:

1. The attacker gains initial access to the system with low-level user privileges
2. A malicious application or script opens a handle to the Kernel Streaming WOW Thunk Service Driver
3. The application sends specially crafted IOCTL requests containing oversized data payloads
4. The driver processes these requests without proper bounds validation, causing a heap buffer overflow
5. The overflow corrupts kernel heap metadata or adjacent memory structures
6. Through careful heap manipulation, the attacker achieves arbitrary code execution in kernel context
7. The attacker's code runs with SYSTEM privileges, providing complete control over the affected host

The exploitation complexity is considered low as the vulnerability can be triggered reliably once the appropriate IOCTL parameters are identified.

Detection Methods for CVE-2024-38054

Indicators of Compromise

• Unusual process behavior with unexpected privilege elevation from low-privileged user accounts
• Abnormal IOCTL requests targeting Kernel Streaming drivers with malformed or oversized data buffers
• Suspicious processes spawning with SYSTEM privileges from user context
• Windows Event Log entries indicating driver crashes or kernel memory corruption events
• Evidence of heap spray or heap grooming techniques preceding privilege escalation

Detection Strategies

• Monitor for processes making unusual IOCTL calls to Kernel Streaming WOW Thunk Service Driver components
• Implement kernel-level monitoring to detect heap corruption or abnormal memory access patterns
• Deploy endpoint detection solutions that can identify privilege escalation attempts from low-privileged processes
• Enable Windows Exploit Protection and monitor for mitigation triggers related to heap buffer overflows
• Use SIEM rules to correlate low-privileged user activity with subsequent SYSTEM-level process creation

Monitoring Recommendations

• Enable detailed Windows Security Event logging for process creation events (Event ID 4688) with command line auditing
• Configure Sysmon to capture driver load events and IOCTL activity patterns
• Monitor for anomalous parent-child process relationships indicating privilege escalation
• Implement file integrity monitoring on critical system files that could be modified post-exploitation

How to Mitigate CVE-2024-38054

Immediate Actions Required

• Apply the July 2024 Microsoft security updates immediately to all affected Windows systems
• Prioritize patching for systems with multiple user accounts or those accessible to untrusted users
• Review and restrict local user privileges following the principle of least privilege
• Enable Windows Defender Credential Guard on supported systems to limit post-exploitation impact
• Implement application whitelisting to prevent execution of unauthorized applications that could exploit this vulnerability

Patch Information

Microsoft has released security updates addressing CVE-2024-38054 as part of the July 2024 Patch Tuesday release. The official security advisory is available at the Microsoft Security Response Center. Organizations should apply the appropriate updates for their specific Windows versions as documented in the advisory.

The patches address the underlying bounds checking issues in the Kernel Streaming WOW Thunk Service Driver, preventing the heap buffer overflow condition from being exploited.

Workarounds

• If immediate patching is not possible, consider restricting local access to systems running affected Windows versions
• Implement strict user privilege management to limit the number of accounts with local access
• Deploy application control solutions to prevent unauthorized executables from running
• Enable Windows Defender Exploit Protection with mandatory ASLR and Control Flow Guard for additional defense-in-depth

# Verify Windows Update status and check for pending security updates
# Run in elevated PowerShell
Get-WindowsUpdate -KBArticleID KB5040442
Get-HotFix | Where-Object {$_.HotFixID -like "KB504*"} | Sort-Object InstalledOn -Descending