CVE-2025-53149 in Windows
Summary
by MITRE • 08/12/2025
Heap-based buffer overflow in Kernel Streaming WOW Thunk Service Driver allows an authorized attacker to elevate privileges locally.
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Analysis
by VulDB Data Team • 11/22/2025
The vulnerability identified as CVE-2025-53149 represents a critical heap-based buffer overflow within the Kernel Streaming WOW Thunk Service Driver component of the Windows operating system. This flaw exists in the kernel-mode driver responsible for handling multimedia streaming operations through the Windows on Windows (WOW) compatibility layer, which enables 32-bit applications to run on 64-bit Windows systems. The issue manifests when the driver processes malformed input data through the WOW thunking mechanism, creating a condition where attacker-controlled data can overwrite adjacent memory locations in the heap allocation space. This particular vulnerability is classified under CWE-121 Heap-based Buffer Overflow, which occurs when a program writes data beyond the boundaries of a heap-allocated buffer, potentially allowing arbitrary code execution or privilege escalation. The affected driver operates with elevated privileges in kernel space, making this vulnerability particularly dangerous for local attackers who can leverage it to gain SYSTEM-level access to the target system.
The technical exploitation of this vulnerability requires an authorized attacker with local access to the system, as the flaw does not permit remote code execution. The attacker must be able to execute code within the context of a legitimate user session, typically through a malicious application or service that can trigger the vulnerable code path in the kernel driver. The buffer overflow occurs during the processing of multimedia data streams, specifically when the WOW thunk service handles 32-bit application requests that interact with kernel-mode streaming components. The heap corruption allows for overwriting critical data structures, function pointers, or return addresses, potentially enabling code execution within the kernel context. According to the ATT&CK framework, this vulnerability maps to T1068 Privilege Escalation and T1547 Persistence, as successful exploitation can lead to SYSTEM-level privileges and persistent access to the compromised system. The attack vector involves a local privilege escalation scenario where the attacker's code is executed in kernel mode, bypassing standard user-mode security controls and access restrictions.
The operational impact of CVE-2025-53149 extends beyond simple privilege escalation, as it represents a serious threat to system integrity and security posture. Once successfully exploited, the attacker gains complete control over the target system, enabling them to access all data, install malware, modify system configurations, or establish persistent backdoors. The vulnerability affects systems running Windows versions that include the affected kernel streaming components, particularly those supporting multimedia applications and legacy 32-bit software compatibility. Organizations with systems running older Windows versions or those that have not applied relevant security updates face the highest risk of exploitation. The flaw's nature as a kernel-mode vulnerability means that standard endpoint protection solutions may not detect or prevent the exploitation, as the malicious activity occurs at a lower system level where traditional security controls have limited visibility. Additionally, the vulnerability's exploitation can potentially lead to information disclosure, system instability, or denial of service conditions, making it a comprehensive security threat that requires immediate attention and remediation.
Mitigation strategies for CVE-2025-53149 should focus on both immediate patching and operational security measures. Microsoft has released security updates addressing this vulnerability, and system administrators should prioritize applying the relevant patches to all affected systems. The patching process requires careful testing in production environments to ensure compatibility with existing applications and services, particularly those relying on multimedia streaming capabilities. Organizations should also implement additional security controls such as enabling kernel-mode code integrity checks, restricting user privileges, and monitoring for suspicious kernel-mode activities through advanced threat detection solutions. The principle of least privilege should be enforced, limiting the number of users with local access to systems that may be vulnerable. System administrators should also consider implementing application whitelisting policies to prevent unauthorized execution of potentially malicious code that could trigger the vulnerability. Regular security assessments and vulnerability scanning should be conducted to identify systems that may be running outdated versions of the affected driver components. The vulnerability also highlights the importance of maintaining up-to-date security practices and ensuring that all system components, particularly those operating at kernel level, receive timely security updates and patches to protect against known exploits.