CVE-2019-9337 in Android
Summary
by MITRE
In libavc there is a possible information disclosure due to uninitialized data. This could lead to remote information disclosure with no additional execution privileges needed. User interaction is needed for exploitation. Product: AndroidVersions: Android-10Android ID: A-112204376
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Analysis
by VulDB Data Team • 09/12/2020
The vulnerability identified as CVE-2019-9337 resides within the libavc component of Android systems, specifically affecting Android 10 releases. This issue represents a critical information disclosure flaw that stems from the improper handling of uninitialized data structures within the video codec processing pipeline. The vulnerability manifests when the system fails to properly initialize memory segments before processing video data, creating potential pathways for sensitive information leakage. The flaw is particularly concerning as it operates without requiring any special execution privileges, making it accessible to attackers who can leverage user interaction to trigger the exploit. The Android security team assigned this vulnerability the identifier A-112204376, highlighting its significance within the Android security framework.
The technical root cause of this vulnerability lies in the improper initialization of memory buffers within the libavc library's video processing functions. When processing video streams, the system allocates memory segments that should be properly initialized before data is written to them. However, in certain code paths, these memory areas retain uninitialized data from previous operations or system memory, creating a scenario where sensitive information from other processes or system components could be inadvertently exposed through the video processing pipeline. This type of vulnerability maps directly to CWE-457, which describes "Use of uninitialized variable" and falls under the broader category of information exposure vulnerabilities. The uninitialized data could contain cryptographic keys, personal identification information, or other sensitive system data that persists in memory and becomes accessible through the flawed processing mechanism.
The operational impact of this vulnerability extends beyond simple information disclosure, as it creates potential attack vectors for more sophisticated exploitation techniques. An attacker could leverage this vulnerability to perform remote information gathering without requiring elevated privileges or special execution rights. The requirement for user interaction suggests that the exploit would likely occur through social engineering or phishing campaigns where users are诱导 to interact with malicious media content. This could result in unauthorized access to sensitive data stored in memory, potentially including user credentials, personal information, or proprietary data. The vulnerability's classification under the ATT&CK framework would place it within the information gathering phase, specifically targeting memory exposure techniques that could lead to further compromise of the affected system.
Mitigation strategies for CVE-2019-9337 focus primarily on updating the affected Android system components to versions that properly initialize memory buffers before processing video data. Android security patches released in subsequent updates addressed the uninitialized data handling issue by implementing proper memory initialization routines within the libavc library. Organizations should ensure their Android devices are updated to the latest security patches, particularly those released after the vulnerability disclosure. Additional defensive measures include implementing network-based filtering to restrict access to potentially malicious media content, deploying mobile device management solutions that enforce security policies, and conducting regular security assessments of video processing applications. The vulnerability serves as a reminder of the importance of proper memory management practices in system components that handle sensitive data, particularly in mobile environments where user interaction with multimedia content is common.