CVE-2019-2076 in Android
Summary
by MITRE
In libxaac there is a possible out of bounds write due to a missing bounds check. This could lead to remote code execution with no additional execution privileges needed. User interaction is needed for exploitation. Product: AndroidVersions: Android-10Android ID: A-115907334
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Analysis
by VulDB Data Team • 09/11/2020
The vulnerability identified as CVE-2019-2076 resides within the libxaac library component of Android systems, specifically affecting Android 10 implementations. This flaw represents a critical security weakness that stems from inadequate input validation mechanisms within the audio processing subsystem. The issue manifests as a missing bounds check during audio frame processing, creating a scenario where maliciously crafted audio data could trigger memory corruption. The vulnerability is classified under CWE-129 as an insufficient bounds check, which directly enables buffer overflow conditions that can be exploited remotely.
The technical exploitation of this vulnerability requires user interaction, typically through the playback of specially crafted audio files or media content that triggers the affected libxaac processing path. When the audio decoder encounters malformed input data, the absence of proper bounds checking allows the processor to write data beyond the allocated memory buffer boundaries. This memory corruption can overwrite adjacent memory locations including function pointers, return addresses, or other critical program data structures. The remote code execution capability arises because the attacker can manipulate these overwritten memory locations to redirect program execution flow to malicious code, potentially executing arbitrary instructions with the privileges of the affected audio processing service.
From an operational security perspective, this vulnerability presents a significant risk to Android devices as it requires no elevated privileges for exploitation and can be triggered through standard media playback scenarios. The attack surface is broad since audio processing occurs frequently during normal device operation, including when users play music, videos, or receive multimedia content through various applications. The vulnerability affects the Android framework's audio decoding capabilities, making it particularly concerning as audio processing is a fundamental system function. Security researchers have categorized this issue under the ATT&CK framework as a privilege escalation vector through application-level exploitation, with potential for lateral movement within the device's security boundaries.
The mitigation strategies for CVE-2019-2076 involve immediate patching of the affected Android system components through standard security updates. Organizations should implement network-based controls to restrict access to untrusted audio content and consider application whitelisting policies for audio processing applications. Device manufacturers should prioritize the deployment of security patches and conduct thorough regression testing to ensure that the fixes do not introduce compatibility issues with legitimate audio processing functionality. Additionally, users should maintain updated device firmware and exercise caution when downloading or playing multimedia content from untrusted sources, particularly in environments where security controls may be less robust. The vulnerability serves as a reminder of the critical importance of input validation in multimedia processing components and the need for comprehensive security testing of system libraries that handle user-provided data.