A critical security vulnerability, identified as CVE-2025-49666, has been discovered in the Windows Kernel, specifically affecting the Setup and Boot Event Collection components. This flaw is a heap-based buffer overflow that allows an authorized attacker to execute arbitrary code over a network. The vulnerability has been assigned a CVSS score of 7.5, indicating a high severity level.
Technical Details
The vulnerability arises from improper handling of memory allocations within the Windows Kernel during the setup and boot event collection processes. A heap-based buffer overflow occurs when the system allocates more memory than is available in the heap, leading to memory corruption. This corruption can be exploited by an attacker to execute arbitrary code with elevated privileges.
Attack Vector
To exploit this vulnerability, an attacker must have authorized access to the target system. Once access is obtained, the attacker can send specially crafted network packets to the vulnerable components, triggering the buffer overflow and allowing for remote code execution. This could lead to full system compromise, data exfiltration, or disruption of services.
Affected Systems
The following Windows versions are affected by CVE-2025-49666:
- Windows Server 2016
- Windows Server 2019
- Windows Server 2022
- Windows 10 (versions 1507, 1607, 1809, 21H2, 22H2)
- Windows 11 (versions 22H2, 23H2, 24H2)
Mitigation and Recommendations
Microsoft has released security updates addressing this vulnerability. Administrators are strongly advised to apply these patches immediately to prevent potential exploitation. Additionally, it is recommended to:
- Regularly monitor and audit system logs for unusual activity.
- Restrict network access to critical systems and services.
- Implement least privilege access controls to minimize potential attack surfaces.
CVE-2025-49666 represents a significant security risk due to its potential for remote code execution through a heap-based buffer overflow in the Windows Kernel. Prompt application of the provided security updates and adherence to best practices in system security are essential to protect affected systems from potential attacks.
Source: MSRC Security Update Guide - Microsoft Security Response Center