CVE-2025-21011

Vulnerability

Details

CVE-2025-21011 is an improper access control vulnerability affecting the SemSensorService component in Samsung Galaxy Watch devices prior to the SMR Aug-2025 Release 1 security update. The root cause is that the service fails to enforce adequate permission checks, allowing unprivileged local access to sensitive sensor data streams.

Exploitation

The attack surface is local; an attacker must have physical access to the watch or be able to run code on the device (e.g., through a malicious application). No special privileges beyond basic local access are required, as the SemSensorService does not restrict access to motion and body sensor information appropriately.

Impact

A successful exploit enables a local attacker to read motion data (e.g., accelerometer, gyroscope) and body sensor data (e.g., heart rate, bioimpedance) without the user's knowledge or consent. This leakage can compromise user privacy by revealing activity patterns, health metrics, and potentially other biometric information.

Mitigation

Samsung has addressed the vulnerability in the SMR Aug-2025 Release 1 update for Galaxy Watch models. Users are advised to install the update as soon as it becomes available. The official advisory from Samsung Mobile Security ([1]) provides the relevant patch details.

References

[1] Samsung Mobile Security: SMR Aug-2025 Release 1