CVE-2025-54912 is a high-severity use-after-free vulnerability (CWE-416) affecting Microsoft Windows 10 Version 1809 (build 10.0.17763.0). This vulnerability resides in the Windows BitLocker component, which is responsible for full disk encryption and protecting data confidentiality on Windows devices. The flaw allows an authorized local attacker to exploit a use-after-free condition, where memory is accessed after it has been freed, potentially leading to arbitrary code execution or memory corruption. Exploiting this vulnerability enables the attacker to elevate their privileges on the affected system without requiring user interaction. The CVSS v3.1 base score is 7.8, reflecting high impact on confidentiality, integrity, and availability, with low attack complexity and requiring only low privileges. Although there are no known exploits in the wild yet and no patches currently available, the vulnerability poses a significant risk due to the critical role of BitLocker in protecting sensitive data and the potential for privilege escalation. The vulnerability's exploitation could allow attackers to bypass security controls, access encrypted data, or execute malicious code with elevated rights, undermining system security and data protection.

For European organizations, this vulnerability presents a serious threat, especially for enterprises and government entities relying on Windows 10 Version 1809 with BitLocker enabled for data protection and regulatory compliance (e.g., GDPR). Successful exploitation could lead to unauthorized access to sensitive or personal data, breach of confidentiality, and potential disruption of critical services. The elevation of privileges could facilitate further lateral movement within networks, enabling attackers to compromise additional systems or exfiltrate data. This is particularly concerning for sectors with high security requirements such as finance, healthcare, and public administration. The lack of a patch and the presence of an exploit vector that requires only local access means insider threats or attackers who gain initial footholds could leverage this vulnerability to escalate privileges and deepen their access. The impact extends to undermining trust in encryption protections, potentially exposing encrypted data to compromise.

European organizations should immediately identify and inventory systems running Windows 10 Version 1809 with BitLocker enabled. Given the absence of a patch, organizations should implement strict access controls to limit local user privileges and restrict physical and remote access to affected systems. Employing application whitelisting and endpoint detection and response (EDR) solutions can help detect anomalous behaviors indicative of exploitation attempts. Organizations should also consider disabling BitLocker temporarily on vulnerable systems if operationally feasible and safe, or upgrading affected systems to a supported and patched Windows version where this vulnerability is resolved. Regularly monitoring security advisories from Microsoft and applying patches promptly once available is critical. Additionally, enforcing multi-factor authentication and network segmentation can reduce the risk of privilege escalation leading to broader network compromise.