CVE-2025-54911 is a use-after-free vulnerability classified under CWE-416 affecting the BitLocker component of Microsoft Windows 10 Version 1809 (build 10.0.17763.0). BitLocker is a full disk encryption feature designed to protect data by encrypting entire volumes. The vulnerability arises from improper memory management where a pointer to a freed object is used, leading to undefined behavior that an attacker can exploit to execute arbitrary code or escalate privileges. The attack vector is local, requiring the attacker to have authorized access to the system and some user interaction, such as running a crafted application or script. Exploiting this flaw allows an attacker to elevate their privileges from a limited user to SYSTEM level, thereby gaining full control over the affected machine. The CVSS v3.1 score of 7.3 reflects a high severity, with high impact on confidentiality, integrity, and availability, moderate attack complexity, and the need for local privileges and user interaction. No public exploits have been reported yet, but the vulnerability is critical due to BitLocker's role in securing sensitive data. The lack of available patches at the time of publication necessitates immediate mitigation strategies to reduce risk. This vulnerability is particularly concerning for environments where Windows 10 Version 1809 is still in use, especially in enterprise and government sectors relying on BitLocker for data protection.

For European organizations, the impact of CVE-2025-54911 can be severe. Successful exploitation leads to local privilege escalation, enabling attackers to bypass security controls and access sensitive encrypted data protected by BitLocker. This compromises data confidentiality and integrity, potentially exposing personal data protected under GDPR, intellectual property, and critical operational information. The availability of systems could also be affected if attackers deploy ransomware or destructive payloads after privilege escalation. Organizations in finance, healthcare, government, and critical infrastructure sectors are at heightened risk due to the sensitive nature of their data and regulatory requirements. Legacy systems still running Windows 10 Version 1809 are particularly vulnerable, and the presence of BitLocker encryption increases the attack surface. The threat could lead to significant financial losses, reputational damage, and regulatory penalties if exploited. Given the local attack vector, insider threats or attackers who gain initial access through phishing or other means could leverage this vulnerability to escalate privileges and move laterally within networks.

1. Immediately inventory and identify all systems running Windows 10 Version 1809, prioritizing those with BitLocker enabled. 2. Apply any official patches or security updates from Microsoft as soon as they become available. 3. Until patches are available, restrict local user privileges to the minimum necessary, avoiding granting administrative rights to standard users. 4. Disable or limit BitLocker features where feasible, especially on systems with multiple users or shared access. 5. Implement strict application whitelisting to prevent execution of unauthorized or suspicious code that could exploit the vulnerability. 6. Enhance monitoring and logging for unusual privilege escalation attempts or suspicious local activity on affected systems. 7. Conduct user awareness training to reduce the risk of social engineering attacks that could lead to initial access. 8. Consider upgrading affected systems to a supported and patched Windows version to eliminate exposure. 9. Use endpoint detection and response (EDR) tools to detect and respond to exploitation attempts in real time. 10. Regularly back up critical data and verify the integrity of backups to ensure recovery capability in case of compromise.