CVE-2026-20962 is a vulnerability classified under CWE-908, indicating the use of an uninitialized resource within the Dynamic Root of Trust for Measurement (DRTM) component of Microsoft Windows 11 Version 25H2 (build 10.0.26200.0). DRTM is a security feature designed to establish a trusted environment during system boot or runtime by measuring and verifying system integrity. The flaw arises because a resource within DRTM is not properly initialized before use, which can lead to leakage of sensitive information. An attacker with authorized local access and high privileges can exploit this vulnerability to disclose confidential data from memory or system state that should otherwise be protected. The vulnerability does not affect system integrity or availability but compromises confidentiality. Exploitation requires local access with elevated privileges, and no user interaction is needed. The CVSS v3.1 score of 4.4 reflects a medium severity, primarily due to the local attack vector and the requirement for high privileges. No public exploits or patches are currently available, but the vulnerability is publicly disclosed and should be addressed promptly to prevent potential misuse.

For European organizations, the primary impact of CVE-2026-20962 is the potential unauthorized disclosure of sensitive information on Windows 11 systems running version 25H2. This can affect confidentiality of corporate data, intellectual property, or personal data protected under GDPR. Organizations with high-value data or critical infrastructure relying on Windows 11 endpoints are at risk of insider threats or attackers who have gained elevated local access. Although the vulnerability does not allow remote exploitation or system disruption, the information disclosure could facilitate further attacks or data breaches. The impact is particularly significant for sectors such as finance, healthcare, government, and critical infrastructure where data confidentiality is paramount. The medium severity rating suggests that while the risk is not critical, it should not be ignored, especially in environments with multiple privileged users or where endpoint security controls are weak.

1. Limit local administrative privileges strictly to trusted personnel and enforce the principle of least privilege to reduce the risk of exploitation. 2. Implement robust endpoint detection and response (EDR) solutions to monitor and alert on suspicious privileged activities. 3. Employ application whitelisting and control tools to prevent unauthorized code execution by local users. 4. Regularly audit and review local user accounts and their privilege levels to identify and remove unnecessary elevated access. 5. Once Microsoft releases a security patch for this vulnerability, prioritize its deployment across all affected Windows 11 systems. 6. Use hardware-based security features such as TPM and secure boot to strengthen the trusted computing base and reduce attack surface. 7. Educate system administrators and privileged users about the risks of local privilege misuse and the importance of secure operational practices. 8. Consider network segmentation to isolate critical systems and limit lateral movement opportunities for attackers with local access.