CVE-2025-21013 is a medium-severity vulnerability identified in Samsung Mobile Devices, specifically affecting the SemSensorManager component used in Galaxy Watch devices prior to the SMR (Security Maintenance Release) August 2025 Release 1. The vulnerability is classified under CWE-284, which corresponds to improper access control. This flaw allows a local attacker to bypass intended access restrictions and gain unauthorized access to sensitive user information related to outdoor exercise and sleep time data. The vulnerability does not require any privileges or user interaction to exploit, but it is limited to local access, meaning the attacker must have physical or local access to the device. The CVSS v3.1 base score is 6.2, reflecting a medium severity level, with the vector indicating local attack vector (AV:L), low attack complexity (AC:L), no privileges required (PR:N), no user interaction (UI:N), unchanged scope (S:U), high confidentiality impact (C:H), and no impact on integrity or availability (I:N/A:N). Although no known exploits are currently reported in the wild, the exposure of sensitive health-related data could have privacy implications. The vulnerability arises from insufficient enforcement of access control policies in the SemSensorManager, which manages sensor data collection and access on Galaxy Watch devices. This flaw could allow malicious local applications or users to retrieve sensitive biometric and activity data without proper authorization, potentially leading to privacy violations or targeted profiling of users based on their health and activity patterns.

For European organizations, especially those involved in healthcare, fitness, or employee wellness programs that utilize Samsung Galaxy Watch devices, this vulnerability poses a significant privacy risk. Unauthorized access to sensitive health and activity data could lead to breaches of GDPR regulations, resulting in legal and financial penalties. Organizations deploying these devices for workforce monitoring or health tracking may face reputational damage if such data is exposed. Additionally, attackers with local access could leverage this vulnerability to gather personal lifestyle information that could be used for social engineering or targeted attacks. While the vulnerability does not directly impact device integrity or availability, the confidentiality breach alone is critical in sectors where data privacy is paramount. Furthermore, the lack of known exploits in the wild suggests that proactive mitigation is essential to prevent future exploitation, especially in environments where devices may be physically accessible to untrusted individuals.

To mitigate this vulnerability, European organizations should prioritize updating affected Samsung Galaxy Watch devices to the SMR August 2025 Release 1 or later, where the access control issue has been addressed. Until patches are applied, organizations should enforce strict physical security controls to limit local access to devices, including secure storage and restricted device handling policies. Additionally, organizations should audit installed applications on these devices to ensure no unauthorized or potentially malicious apps are present that could exploit local access to sensor data. Implementing endpoint management solutions that monitor device configurations and enforce security policies can help detect and prevent exploitation attempts. For environments where sensitive health data is collected, consider encrypting data at rest and in transit and applying strict access controls at the application and network levels. User awareness training on the risks of local device access and the importance of device security can further reduce the risk of exploitation. Finally, organizations should monitor Samsung security advisories for any updates or additional patches related to this vulnerability.