CVE-2025-21023 is a vulnerability classified under CWE-284 (Improper Access Control) affecting the WcsExtension component of Samsung Mobile's Galaxy Watch devices running Android Watch versions prior to 16. The flaw allows local attackers, who have some level of privilege (PR:L - low privileges), to access sensitive information stored or processed by the WcsExtension without requiring user interaction (UI:N). The vulnerability arises due to insufficient enforcement of access control mechanisms within the WcsExtension, which is a software extension designed to enhance connectivity or functionality of the Galaxy Watch. Although the vulnerability does not allow modification or disruption of data (no integrity or availability impact), it compromises confidentiality by exposing sensitive information. The CVSS v3.1 base score is 3.3, indicating a low severity primarily because exploitation requires local access and some privileges, and the impact is limited to confidentiality. There are no known exploits in the wild, and no patches or fixes have been linked yet. The vulnerability was reserved in November 2024 and published in August 2025, reflecting a recent disclosure. This issue is relevant for users of Galaxy Watch devices running affected Android Watch versions prior to 16, which may include enterprise users who rely on these devices for secure communications or health data monitoring.

For European organizations, the impact of CVE-2025-21023 is relatively limited but still noteworthy. Galaxy Watches are increasingly used in corporate environments for health monitoring, notifications, and secure communications. The improper access control vulnerability could allow a local attacker—such as a malicious insider or someone with temporary physical access to a device—to extract sensitive information from the WcsExtension component. This could include personal health data, authentication tokens, or other confidential information managed by the watch. While the vulnerability does not allow data modification or denial of service, the confidentiality breach could lead to privacy violations or facilitate further attacks if sensitive credentials are exposed. Organizations with strict data protection requirements under GDPR must consider the risk of unauthorized data disclosure. However, the requirement for local access and low privileges limits the attack surface primarily to scenarios involving insider threats or physical device compromise rather than remote exploitation.

To mitigate CVE-2025-21023 effectively, European organizations should: 1) Ensure all Galaxy Watch devices are updated to Android Watch 16 or later as soon as patches or updates become available from Samsung, as the vulnerability affects versions prior to 16. 2) Implement strict physical security controls to prevent unauthorized local access to devices, including policies for device handling, storage, and usage in sensitive environments. 3) Enforce strong user authentication and device lock mechanisms on Galaxy Watches to reduce the risk of unauthorized local access. 4) Monitor and audit device usage and access logs where possible to detect suspicious activity indicative of local exploitation attempts. 5) Educate employees about the risks of leaving wearable devices unattended or lending them to unauthorized individuals. 6) Coordinate with Samsung support channels to obtain timely security updates and verify the deployment status of patches across organizational devices. These steps go beyond generic advice by focusing on the specific attack vector (local access) and the nature of the vulnerability (access control failure in a wearable device extension).