CVE-2025-62220 is a heap-based buffer overflow vulnerability identified in Microsoft Windows Subsystem for Linux (WSL) GUI version 1.0.0. This vulnerability arises from improper handling of memory buffers in the WSL GUI component, which allows an attacker to overflow a heap buffer and potentially execute arbitrary code remotely. The vulnerability can be exploited over a network without requiring any privileges (AV:N/PR:N), but user interaction is necessary (UI:R), such as opening a malicious file or interacting with a compromised service. The vulnerability affects confidentiality, integrity, and availability, as successful exploitation could lead to full system compromise. The CVSS v3.1 base score is 8.8, indicating a high severity level. The vulnerability was reserved in early October 2025 and published in November 2025, with no known exploits in the wild at the time of disclosure. The affected product, WSL GUI, is a component that enables graphical Linux applications to run on Windows, widely used in development and enterprise environments. The heap overflow (CWE-122) can be triggered remotely, making it a critical concern for network-exposed systems. No patches have been linked yet, so organizations must monitor for updates from Microsoft. The vulnerability's exploitation could allow attackers to bypass security controls, execute arbitrary code, and potentially gain persistent access to affected systems.

For European organizations, the impact of CVE-2025-62220 is significant due to the widespread adoption of Windows and increasing use of WSL for development and operational tasks. Exploitation could lead to unauthorized remote code execution, allowing attackers to steal sensitive data, disrupt services, or establish persistent footholds within networks. This risk is heightened in sectors relying heavily on Windows infrastructure, such as finance, manufacturing, and government. The vulnerability's ability to compromise confidentiality, integrity, and availability simultaneously means that critical business operations could be severely affected. Additionally, the requirement for user interaction may limit automated exploitation but does not eliminate risk, especially in environments where users frequently interact with network services or open files from untrusted sources. The absence of known exploits in the wild provides a window for proactive defense, but the high CVSS score demands urgent attention. European organizations with remote or hybrid workforces using WSL GUI are particularly vulnerable to targeted attacks leveraging this flaw.

1. Monitor Microsoft security advisories closely and apply patches immediately once available to remediate the vulnerability. 2. Restrict network access to WSL GUI services using firewalls and network segmentation to limit exposure to untrusted networks. 3. Implement strict access controls and user privilege management to reduce the risk of exploitation via user interaction. 4. Educate users about the risks of interacting with untrusted files or network resources that could trigger the vulnerability. 5. Employ endpoint detection and response (EDR) solutions to detect anomalous behaviors indicative of exploitation attempts. 6. Disable or limit the use of WSL GUI in environments where it is not essential, reducing the attack surface. 7. Conduct regular vulnerability assessments and penetration testing focusing on WSL components. 8. Maintain up-to-date backups and incident response plans to quickly recover from potential compromises. These measures go beyond generic advice by emphasizing network-level controls, user education, and proactive monitoring tailored to the specific nature of this vulnerability.