CVE-2023-40418 in watchOS
Summary
by MITRE • 09/27/2023
An authentication issue was addressed with improved state management. This issue is fixed in watchOS 10. An Apple Watch Ultra may not lock when using the Depth app.
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Analysis
by VulDB Data Team • 11/06/2025
The vulnerability described in CVE-2023-40418 represents a critical authentication flaw within Apple Watch operating system that affects the device's lock mechanism during specific application usage. This issue specifically impacts the watchOS 10 operating system and manifests when users interact with the Depth app, which is designed for underwater navigation and measurement capabilities. The authentication weakness stems from improper state management within the operating system's security framework, creating a window where the device fails to enforce proper locking protocols when transitioning between application contexts. This vulnerability directly relates to the fundamental security principle of maintaining secure session states and proper access controls, particularly in mobile devices where physical security and data protection are paramount.
The technical implementation of this flaw involves the operating system's failure to correctly manage the device's authentication state when the Depth app is active. When users engage with underwater navigation features, the system should maintain proper lock mechanisms to prevent unauthorized access to sensitive data and functionalities. However, the flawed state management prevents the device from properly transitioning to a locked state, potentially exposing user data, navigation parameters, and personal information stored on the device. This issue falls under the category of improper authentication state handling, which is classified as CWE-613 in the Common Weakness Enumeration system, representing insufficient session management that could lead to unauthorized access to protected resources. The vulnerability demonstrates a failure in the operating system's security architecture to maintain consistent authentication boundaries across different application contexts.
The operational impact of this vulnerability extends beyond simple convenience issues to potential security risks for users who rely on Apple Watch for sensitive activities such as underwater navigation, fitness tracking, and personal data management. When the device fails to lock properly during Depth app usage, it creates opportunities for unauthorized individuals to access the device's contents, potentially including personal fitness data, navigation history, and other sensitive information. The risk is particularly elevated in environments where users may be in public spaces or areas where physical security of their wearable device is compromised. This vulnerability can be exploited through the ATT&CK framework's technique T1548.003, which involves bypassing system access controls through improper state management, potentially allowing threat actors to maintain persistent access to the device's resources. The issue represents a significant concern for users who depend on their Apple Watch for both personal and potentially professional underwater activities where data confidentiality is crucial.
Mitigation strategies for this vulnerability require immediate system updates to address the underlying state management issues within watchOS 10. Users should ensure their Apple Watch devices are updated to the latest available firmware version that includes the patch for this authentication flaw. System administrators and security professionals should monitor for the availability of updated watchOS releases and implement mandatory update policies for devices in enterprise environments. Additionally, users should be educated about the potential risks of leaving their devices unlocked during sensitive applications and consider implementing additional security measures such as passcode requirements or biometric authentication settings that provide multiple layers of protection. The vulnerability highlights the importance of proper session management in mobile operating systems and underscores the need for comprehensive testing of authentication mechanisms across all application contexts, particularly those involving specialized functionality like underwater navigation where device security is paramount.