CVE-2024-28897 is a vulnerability identified in Microsoft Windows 10 Version 1809 (build 10.0.17763.0) related to improper input validation (CWE-20) that allows bypassing the Secure Boot security feature. Secure Boot is a critical security mechanism designed to ensure that only trusted software is loaded during the system boot process, preventing unauthorized or malicious code from executing before the operating system loads. This vulnerability arises from insufficient validation of input data within the Secure Boot implementation, which could be exploited by an attacker with high privileges on the system to bypass Secure Boot protections. The CVSS v3.1 base score is 6.8 (medium severity), with the vector indicating that the attack requires adjacent network access (AV:A), low attack complexity (AC:L), and high privileges (PR:H). No user interaction is needed (UI:N), and the scope is unchanged (S:U). The impact on confidentiality, integrity, and availability is high (C:H/I:H/A:H), meaning that successful exploitation could lead to full compromise of the system's boot integrity, potentially allowing persistent malware or rootkits to be loaded undetected. There are no known exploits in the wild as of the publication date (April 9, 2024), and no official patches have been linked yet. The vulnerability was reserved on March 13, 2024, and has been enriched by CISA, indicating recognition by US cybersecurity authorities. Given the nature of the vulnerability, exploitation would require an attacker to have already obtained high-level privileges on the target system or have physical/adjacent network access, making it a post-compromise or targeted attack vector rather than a remote initial entry point. The vulnerability affects a legacy Windows 10 version (1809), which is still in use in some environments but is no longer the latest Windows 10 or 11 version.

For European organizations, the impact of CVE-2024-28897 could be significant in environments where Windows 10 Version 1809 is still deployed, especially in critical infrastructure, government, or industrial control systems that rely on Secure Boot to maintain system integrity. Successful exploitation could allow attackers to bypass Secure Boot protections, enabling persistent malware infections, rootkits, or bootkits that are difficult to detect and remove. This undermines the trustworthiness of the boot process and could lead to data breaches, system downtime, or sabotage. The requirement for high privileges and adjacent network access limits the attack surface but also means that attackers who have already compromised internal systems could escalate their control and persistence. European organizations with legacy systems, especially those in sectors with strict compliance requirements (e.g., finance, healthcare, energy), may face increased risk of regulatory penalties and operational disruptions if this vulnerability is exploited. Additionally, the absence of known exploits currently provides a window for proactive mitigation before widespread attacks occur.

1. Upgrade or Patch: Although no official patch links are provided yet, organizations should monitor Microsoft security advisories closely and apply patches as soon as they become available. 2. System Upgrade: Plan and accelerate migration from Windows 10 Version 1809 to supported, up-to-date Windows versions (e.g., Windows 10 22H2 or Windows 11) that have improved Secure Boot implementations and ongoing security support. 3. Privilege Management: Enforce strict access controls and privilege management to prevent attackers from obtaining the high-level privileges required to exploit this vulnerability. 4. Network Segmentation: Limit adjacent network access by segmenting networks, especially isolating legacy systems, to reduce the risk of lateral movement by attackers. 5. Secure Boot Verification: Implement additional monitoring and verification mechanisms for Secure Boot status and integrity, including firmware-level security tools and endpoint detection solutions capable of detecting boot-level tampering. 6. Incident Response Preparedness: Enhance detection capabilities for boot-level compromises and prepare incident response plans that include recovery from Secure Boot bypass scenarios. 7. Physical Security: For systems with physical access risks, ensure hardware security measures to prevent local exploitation. 8. Vulnerability Scanning: Use vulnerability management tools to identify systems running Windows 10 Version 1809 and prioritize them for remediation or upgrade.