CVE-2025-55676 is a vulnerability identified in the USB Video Driver component of Microsoft Windows 11 Version 25H2 (build 10.0.26200.0). The issue is classified under CWE-209, which involves the generation of error messages containing sensitive information. Specifically, when the USB Video Driver encounters certain error conditions, it improperly includes confidential data within the error messages. This leakage can be exploited by an authorized local attacker who has limited privileges on the affected system. The attacker does not require user interaction to trigger the vulnerability, but must have local access and some level of privilege (PR:L). The vulnerability does not affect system integrity or availability but compromises confidentiality by exposing sensitive information that could be leveraged for further attacks or reconnaissance. The CVSS v3.1 base score is 5.5 (medium severity), reflecting the local attack vector, low complexity, and high confidentiality impact. No public exploits or proof-of-concept code have been reported yet, and Microsoft has not released a patch at the time of publication. The vulnerability was reserved in August 2025 and published in October 2025, indicating recent discovery. This flaw highlights the risk of verbose error reporting in system drivers, which can inadvertently disclose internal state or data that should remain protected.

For European organizations, this vulnerability poses a moderate risk primarily to confidentiality. Organizations with Windows 11 Version 25H2 deployed on endpoints or servers that utilize USB video devices (such as webcams or video capture hardware) may have sensitive information exposed through error messages. This could facilitate lateral movement, privilege escalation, or targeted attacks if attackers gain local access. Sectors handling sensitive personal data, intellectual property, or critical infrastructure information are particularly vulnerable. Although the attack requires local privileges, insider threats or malware that gains limited access could exploit this flaw to gather intelligence. The lack of impact on integrity and availability reduces the risk of direct operational disruption but does not eliminate the threat of data leakage. European GDPR compliance and data protection regulations increase the importance of mitigating such confidentiality breaches. The absence of known exploits currently limits immediate risk but does not preclude future exploitation.

Organizations should implement the following specific mitigations: 1) Restrict local user privileges strictly to trusted personnel and minimize the number of users with local access to systems running Windows 11 Version 25H2. 2) Monitor system logs and error messages for unusual or verbose outputs from USB video drivers that could indicate exploitation attempts. 3) Apply principle of least privilege to USB device access, disabling or restricting USB video devices where not necessary. 4) Prepare for patch deployment by tracking Microsoft security advisories and testing updates in controlled environments before wide rollout. 5) Employ endpoint detection and response (EDR) solutions capable of detecting anomalous local activity related to driver errors or information disclosure. 6) Conduct regular security awareness training to reduce insider threat risks. 7) Use application whitelisting and device control policies to prevent unauthorized software or drivers from running. These steps go beyond generic advice by focusing on local access control, monitoring, and device management tailored to the vulnerability context.