CVE-2018-9468 in Android
Summary
by MITRE • 11/20/2024
In query of DownloadManager.java, there is a possible read/write of arbitrary files due to a permissions bypass. This could lead to local information disclosure and file rewriting with no additional execution privileges needed. User interaction is not needed for exploitation.
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Analysis
by VulDB Data Team • 12/18/2024
The vulnerability identified as CVE-2018-9468 resides within the DownloadManager.java component of Android systems, representing a critical permissions bypass flaw that allows unauthorized file access and modification. This issue stems from inadequate input validation and access control mechanisms within the download management subsystem, creating a pathway for malicious actors to read and write arbitrary files on affected devices. The vulnerability specifically affects the query method implementation where proper permission checks fail to validate file access requests, enabling attackers to manipulate system files without requiring elevated privileges or user interaction. The flaw operates at the application level within the Android framework, exploiting weak boundaries between different system components and user applications that should otherwise be isolated from each other.
The technical exploitation of this vulnerability involves leveraging the DownloadManager's query functionality to bypass normal file system access controls, allowing attackers to access sensitive data stored in protected directories or modify critical system files. This permissions bypass occurs when the system fails to properly validate the file paths being requested through the download manager interface, potentially enabling access to files outside the intended scope of the application's permissions. The vulnerability manifests as a lack of proper path validation and access control enforcement, which can be categorized under CWE-255 Credentials Management Weakness and CWE-73 Relative Path Traversal. Attackers can exploit this by crafting malicious download requests that target specific file paths, potentially accessing system configuration files, user data, or even modifying executable components that could lead to further compromise.
The operational impact of CVE-2018-9468 extends beyond simple information disclosure to encompass potential system integrity compromise and data manipulation capabilities. An attacker with access to a device could leverage this vulnerability to read sensitive user data, modify system files, or potentially escalate privileges through file system manipulation. This vulnerability directly relates to the ATT&CK technique T1074 Data Staged, as it enables adversaries to access and manipulate data stored on the device. The lack of user interaction requirements makes this particularly dangerous as it can be exploited automatically without any user awareness or consent, potentially allowing for silent data exfiltration or system file corruption. The vulnerability affects all Android versions that implement the affected DownloadManager.java component, making it a widespread concern across numerous device models and software versions.
Mitigation strategies for this vulnerability require immediate patching of affected Android systems through official security updates provided by device manufacturers and Google. System administrators should ensure that all devices running affected Android versions receive the latest security patches, particularly those addressing framework-level vulnerabilities in the download management system. Organizations should implement network monitoring to detect anomalous download activities that might indicate exploitation attempts, and consider deploying mobile device management solutions that can enforce security policies and prevent unauthorized file access. The vulnerability demonstrates the importance of proper input validation and access control enforcement in system components, highlighting the need for comprehensive security reviews of framework-level code. Additionally, developers should implement proper path sanitization and access control checks in their applications that interact with system services, ensuring that file access requests are properly validated against expected security boundaries.