CVE-2024-38065 is a heap-based buffer overflow vulnerability (CWE-122) identified in Microsoft Windows 10 Version 1809 (build 10.0.17763.0). The flaw specifically targets the Secure Boot security feature, which is designed to ensure that only trusted software is loaded during the system boot process. By exploiting this vulnerability, an attacker can bypass Secure Boot protections, potentially allowing unauthorized code execution at a low level, compromising system integrity and confidentiality. The vulnerability does not require user interaction or privileges, but the attack vector is physical or local, meaning the attacker must have access to the machine or its boot environment. The CVSS 3.1 base score is 6.8, reflecting a medium severity with high impact on confidentiality, integrity, and availability. No public exploits or patches are currently available, but the vulnerability has been officially published and reserved by Microsoft and tracked by CISA. The heap-based buffer overflow could allow an attacker to execute arbitrary code or cause a denial of service, undermining the trust model of Secure Boot and potentially enabling persistent malware or rootkit installation at boot time.

For European organizations, this vulnerability poses a significant risk to systems still running Windows 10 Version 1809, particularly those relying on Secure Boot for platform security. Compromise of Secure Boot can lead to persistent malware infections that survive OS reinstalls, undermining endpoint security and compliance with regulatory requirements such as GDPR. Critical infrastructure sectors like energy, finance, and government, which often use Secure Boot to protect against firmware-level attacks, could face elevated risks of system compromise and data breaches. The requirement for physical or local access limits remote exploitation but does not eliminate risk in environments with shared or poorly secured physical access. The potential for full confidentiality, integrity, and availability impact means attackers could steal sensitive data, alter system configurations, or disrupt operations.

European organizations should prioritize upgrading affected systems to a supported Windows version beyond 1809, as Microsoft no longer provides security updates for this release. In the absence of an official patch, organizations should enforce strict physical security controls to prevent unauthorized local access to devices. Implementing hardware-based protections such as TPM and ensuring Secure Boot is enabled and properly configured can reduce risk. Regularly auditing systems for unauthorized firmware or bootloader modifications can help detect exploitation attempts. Organizations should also review and update endpoint detection and response (EDR) tools to monitor for suspicious boot-time activities. For critical environments, consider isolating legacy systems or migrating workloads to virtualized or cloud environments with stronger security controls.