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, allowing an attacker to overwrite heap memory, which can lead to arbitrary code execution. The flaw is exploitable remotely over a network without requiring authentication, although user interaction is necessary, possibly through crafted network packets or malicious GUI elements. The vulnerability affects the WSL GUI component, which integrates Linux graphical applications within the Windows environment, exposing a new attack surface. The CVSS 3.1 score of 8.8 reflects high impact on confidentiality, integrity, and availability, indicating that successful exploitation could compromise system control, leak sensitive data, or cause denial of service. No patches or known exploits are currently available, but the vulnerability's nature suggests a high risk of future exploitation. The vulnerability is tracked under CWE-122, a common weakness related to heap-based buffer overflows, which are often exploited to execute arbitrary code or escalate privileges. The vulnerability was reserved in early October 2025 and published in November 2025, indicating recent discovery. The lack of patches necessitates immediate defensive actions to mitigate risk.

For European organizations, the impact of CVE-2025-62220 is significant due to widespread use of Windows environments combined with increasing adoption of WSL for development and operational tasks. Exploitation could lead to unauthorized remote code execution, enabling attackers to gain control over affected systems, exfiltrate sensitive data, disrupt services, or move laterally within networks. Critical sectors such as finance, manufacturing, healthcare, and government agencies that rely on Windows and Linux interoperability are particularly vulnerable. The vulnerability's remote exploitability without authentication increases the attack surface, especially for organizations exposing WSL GUI services or related network ports. The requirement for user interaction may limit automated exploitation but does not eliminate risk, as phishing or social engineering could trigger the attack. The absence of patches means organizations must rely on compensating controls, increasing operational complexity and risk. Additionally, the integration of WSL GUI in enterprise environments means that attackers could leverage this vulnerability to bypass traditional Windows security controls, complicating incident response and recovery efforts.

1. Immediately restrict network exposure of systems running WSL GUI by implementing strict firewall rules and network segmentation to limit access only to trusted users and devices. 2. Disable or uninstall the WSL GUI component where it is not essential, especially on critical or internet-facing systems, to eliminate the attack vector. 3. Educate users about the risks of interacting with unsolicited network content or GUI elements that could trigger the vulnerability, reducing the likelihood of successful user interaction. 4. Monitor network traffic and system logs for unusual activity related to WSL GUI processes, including unexpected network connections or crashes, to detect potential exploitation attempts early. 5. Employ endpoint detection and response (EDR) solutions capable of identifying heap-based buffer overflow exploitation techniques and anomalous process behavior. 6. Maintain up-to-date backups and incident response plans tailored to potential WSL GUI compromise scenarios. 7. Stay informed on Microsoft’s security advisories and apply patches promptly once available. 8. Consider deploying application whitelisting and privilege restrictions to limit the impact of potential code execution. 9. For development environments, isolate WSL GUI usage from production networks to minimize risk exposure. 10. Collaborate with IT and security teams to audit and inventory all systems running WSL GUI to prioritize mitigation efforts.