CVE-2020-0258 in Android
Summary
by MITRE
In stopZygoteLocked of AppZygote.java, there is an insufficient cleanup. This could lead to local information disclosure in the application that is started next with no additional execution privileges needed. User interaction is not needed for exploitation.Product: AndroidVersions: Android-10Android ID: A-157598956
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Analysis
by VulDB Data Team • 08/12/2020
The vulnerability identified as CVE-2020-0258 resides within the Android operating system's application zygote process management mechanism, specifically in the stopZygoteLocked method of the AppZygote.java component. This flaw represents a critical information disclosure vulnerability that stems from inadequate resource cleanup procedures during the zygote process termination sequence. The zygote process serves as the foundation for all Android application processes, acting as a template that is forked to create new application instances. When the system attempts to terminate a zygote process through the stopZygoteLocked method, insufficient cleanup operations leave behind sensitive data structures and memory segments that persist beyond the intended scope of the process lifecycle.
The technical nature of this vulnerability aligns with CWE-224, which addresses insufficient cleanup of sensitive data in the context of process management and resource handling. The flaw occurs during the transition between application execution contexts where the zygote process should properly release all associated resources including memory mappings, file descriptors, and potentially sensitive data that was previously loaded into the process space. The persistence of this information occurs because the cleanup mechanism fails to properly invalidate or clear memory regions that were previously utilized by the zygote process, creating a potential information leak scenario.
From an operational standpoint, this vulnerability presents a significant risk to Android devices as it enables local information disclosure without requiring any additional privileges or user interaction for exploitation. The attack vector is particularly concerning because it leverages the legitimate process management functionality of the Android system to create a persistent information leak that affects subsequent application launches. When a new application is started after the vulnerable zygote process has been terminated, it may inherit or access memory segments that contain sensitive information from the previously terminated process, potentially exposing credentials, application data, or system configuration details.
The exploitation of this vulnerability follows patterns consistent with the attack techniques described in the MITRE ATT&CK framework under the T1005 data hijacking technique, where adversaries access data that should not be accessible to the current process context. The lack of user interaction requirements makes this vulnerability particularly dangerous as it can be exploited automatically during normal device operation without any deliberate user action. This characteristic places the vulnerability in a high-risk category for mobile environments where users may not actively monitor or control all application processes that are launched through the system's zygote management system.
The mitigation strategies for this vulnerability should focus on implementing proper resource cleanup mechanisms within the stopZygoteLocked method and related zygote process management functions. System updates and patches must ensure that all memory segments, file descriptors, and data structures are properly invalidated and cleared when terminating zygote processes. Additionally, the implementation should include memory sanitization routines that prevent any residual data from being accessible to subsequent application processes. Organizations should also consider implementing process isolation mechanisms and monitoring systems that can detect anomalous memory access patterns that might indicate information leakage from terminated processes. The vulnerability demonstrates the critical importance of proper resource management in system-level components and the potential for seemingly benign process management functions to create significant security implications when cleanup operations are inadequate.