CVE-2017-15534 in App Lock
Summary
by MITRE
The Norton App Lock prior to version 1.3.0.13 can be susceptible to an authentication bypass exploit. In this type of circumstance, the exploit can allow the user to kill the app to prevent it from locking the device, thereby allowing the individual to gain device access.
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Analysis
by VulDB Data Team • 01/16/2020
The vulnerability identified as CVE-2017-15534 represents a critical authentication bypass flaw within Norton App Lock software versions prior to 1.3.0.13. This security weakness fundamentally undermines the core functionality of the application which is designed to protect user devices through secure locking mechanisms. The flaw operates at the application lifecycle management level where proper session handling and security enforcement mechanisms fail to maintain consistent protection states. The vulnerability stems from inadequate implementation of security controls that should prevent unauthorized access when the application is designed to lock the device. This type of flaw falls under the broader category of authentication bypass vulnerabilities as defined by CWE-287, which specifically addresses improper authentication mechanisms that allow attackers to circumvent normal access controls.
The technical exploitation of this vulnerability occurs through a simple yet effective method involving the termination of the application process through the operating system's task killer functionality. When users kill the Norton App Lock application process, the security mechanism that should maintain device lock status is disrupted, allowing unauthorized access to the device. This exploit demonstrates a fundamental flaw in how the application manages its own lifecycle and security enforcement states. The vulnerability essentially creates a window of opportunity where the application's protective mechanisms can be disabled through legitimate system functions, bypassing the intended security controls. The flaw represents a failure in proper state management and security enforcement architecture, where the application does not adequately maintain its security posture even when external processes are terminated.
From an operational impact perspective, this vulnerability creates a significant risk for users who rely on Norton App Lock for device security protection. Attackers can exploit this weakness to gain unauthorized access to devices that should be protected, potentially compromising sensitive data, personal information, and application access. The vulnerability affects the fundamental security model of the application, rendering the device protection mechanisms ineffective when the application is terminated. This type of attack vector aligns with ATT&CK technique T1068 which covers "Exploitation for Privilege Escalation" and demonstrates how application-level security bypasses can lead to broader system compromise. The vulnerability essentially allows attackers to execute a form of privilege escalation by manipulating the application's own termination process to gain access to protected device resources.
The mitigation strategy for this vulnerability requires immediate software updates to version 1.3.0.13 or later, which should implement proper security state management and prevent the application from being terminated in ways that bypass its security mechanisms. Organizations and users should also implement additional security controls such as monitoring for unauthorized application termination and ensuring proper process management within the device's security framework. The fix should address the root cause by implementing robust session management that maintains security enforcement even when the application process is interrupted. Security professionals should also consider implementing application whitelisting controls and monitoring for suspicious process termination activities that could indicate exploitation attempts. This vulnerability highlights the importance of proper application security design and the need for comprehensive testing of security mechanisms under various operational conditions, including process termination scenarios that should not compromise overall device security posture.