CVE-2025-55337 is a vulnerability identified in Microsoft Windows 11 Version 25H2 (build 10.0.26200.0) involving improper enforcement of behavioral workflow within the BitLocker encryption feature. BitLocker is designed to protect data confidentiality by encrypting volumes and enforcing access controls. The vulnerability arises from a flaw in the workflow enforcement logic, categorized under CWE-841 (Improper Enforcement of Behavioral Workflow), which allows an attacker with physical access to bypass BitLocker's security mechanisms. This bypass means the attacker can access encrypted data without proper authorization, compromising confidentiality and integrity. The CVSS 3.1 score is 6.1 (medium severity), with the vector indicating physical attack vector (AV:P), low attack complexity (AC:L), no privileges required (PR:N), no user interaction (UI:N), unchanged scope (S:U), high confidentiality and integrity impact (C:H/I:H), and no availability impact (A:N). The exploit does not require authentication or user interaction but does require physical presence, limiting remote exploitation. No known exploits are currently reported in the wild, and no official patches have been published yet. The vulnerability was reserved in August 2025 and published in October 2025. This flaw could be leveraged in targeted physical attacks against devices protected by BitLocker, especially in environments where physical security is less stringent. The absence of patches necessitates immediate mitigation strategies to reduce risk.

For European organizations, this vulnerability poses a significant risk to data confidentiality and integrity, particularly for entities relying on BitLocker to protect sensitive or regulated data. Sectors such as finance, healthcare, government, and critical infrastructure that use Windows 11 25H2 with BitLocker are at heightened risk. An attacker with physical access could bypass encryption protections, leading to unauthorized data disclosure or tampering. This could result in data breaches, regulatory non-compliance (e.g., GDPR violations), reputational damage, and potential financial losses. The requirement for physical access limits widespread exploitation but increases risk in scenarios involving device theft, insider threats, or insufficient physical security controls. The lack of availability impact means operational continuity is less likely to be affected directly. However, the breach of confidentiality and integrity could have cascading effects on trust and compliance frameworks within European organizations.

1. Enforce strict physical security controls to prevent unauthorized access to devices, including secure storage, access logs, and surveillance in sensitive areas. 2. Utilize hardware-based security modules such as TPM (Trusted Platform Module) combined with PIN or startup key protections to strengthen BitLocker defenses. 3. Implement multi-factor authentication for device startup where possible to add an additional layer beyond BitLocker. 4. Monitor and audit physical access to devices regularly to detect potential tampering or unauthorized presence. 5. Maintain up-to-date backups of critical data to mitigate impact in case of compromise. 6. Stay alert for official patches or updates from Microsoft and apply them promptly once available. 7. Consider additional encryption layers or endpoint protection solutions that can detect or prevent unauthorized access attempts. 8. Educate employees about the risks of physical device theft and the importance of securing devices, especially in hybrid or remote work environments.