CVE-2018-9420 in Android
Summary
by MITRE • 11/20/2024
In BnCameraService::onTransact of CameraService.cpp, there is a possible information disclosure due to uninitialized data. This could lead to local information disclosure with no additional execution privileges needed. User interaction is not needed for exploitation.
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Analysis
by VulDB Data Team • 11/20/2024
The vulnerability identified as CVE-2018-9420 resides within the BnCameraService::onTransact method implementation in the CameraService.cpp source file of Android's camera service subsystem. This flaw represents a classic case of uninitialized memory access that can potentially expose sensitive information to unauthorized processes. The issue manifests when the camera service handles transaction requests from client applications, specifically during the processing of camera-related operations through the Binder IPC mechanism. The vulnerability is classified under CWE-457 as "Use of Uninitialized Variable" which directly impacts the security posture of Android devices by creating potential information leakage channels.
The technical exploitation of this vulnerability occurs when the camera service processes incoming transactions without properly initializing certain data structures or variables before use. This uninitialized data may contain remnants of previous operations, system memory contents, or sensitive information from other processes that were previously executed on the device. When the service returns responses to client applications or processes system calls, this uninitialized memory content can inadvertently be included in the response data, effectively leaking information that should remain confidential. The vulnerability does not require any special privileges or user interaction for exploitation, making it particularly concerning as it can be triggered by any process with camera service access permissions. This characteristic aligns with ATT&CK technique T1059 where adversaries can leverage existing system services to gain information disclosure capabilities.
The operational impact of CVE-2018-9420 extends beyond simple information disclosure, as the leaked data could potentially contain cryptographic keys, session tokens, user credentials, or other sensitive system information that could be exploited by malicious applications. The local nature of this vulnerability means that any application with camera service access can potentially exploit it, which could include legitimate camera applications, system services, or even malicious apps that have gained appropriate permissions. This information leakage could enable attackers to perform further attacks such as credential harvesting, session hijacking, or privilege escalation. The vulnerability affects Android versions prior to 2018 and represents a fundamental security flaw in how the camera service handles memory initialization during transaction processing. The lack of user interaction requirement for exploitation makes this vulnerability particularly dangerous as it can be triggered automatically during normal device operation without any user awareness.
Mitigation strategies for CVE-2018-9420 should focus on ensuring proper memory initialization practices within the camera service implementation. The most effective approach involves patching the CameraService.cpp source code to properly initialize all variables and data structures before use, particularly those that are returned in transaction responses. System administrators should ensure that devices are updated to the latest Android security patches that address this vulnerability, as the fix typically involves modifying the BnCameraService::onTransact method to include proper initialization of all memory regions before data is processed and returned. Additionally, implementing proper access controls and monitoring for unauthorized camera service access can help detect potential exploitation attempts. The vulnerability highlights the importance of memory safety practices in system services and demonstrates how seemingly minor initialization flaws can create significant security risks. Organizations should also consider implementing runtime monitoring solutions that can detect anomalous data leakage patterns from system services, particularly those that handle sensitive user information or system resources.