CVE-2019-2071 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-117216549
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Analysis
by VulDB Data Team • 09/11/2020
The vulnerability identified as CVE-2019-2071 resides within the libxaac library component of Android systems, specifically affecting Android 10 versions. This issue represents a critical security flaw that stems from insufficient input validation mechanisms within the audio processing framework. The vulnerability manifests as a missing bounds check during audio frame processing, creating a condition where maliciously crafted audio data can trigger memory corruption. The flaw operates at the intersection of multimedia processing and memory safety, making it particularly dangerous as it can be exploited through standard audio playback channels without requiring elevated privileges or special user permissions for initial access.
The technical implementation of this vulnerability demonstrates a classic out-of-bounds write condition that occurs when the libxaac library fails to properly validate the size or boundaries of incoming audio data structures. When processing audio frames, the library does not adequately verify that data pointers remain within allocated memory regions, allowing an attacker to manipulate memory layout through crafted audio content. This type of vulnerability falls under the CWE-129 classification for Improper Validation of Array Index, which is a well-documented weakness in software security practices. The flaw specifically impacts the Advanced Audio Coding (AAC) decoding process where the library processes audio frames without sufficient boundary checking, enabling potential memory corruption that could be leveraged for arbitrary code execution.
From an operational perspective, this vulnerability creates significant risk exposure for Android devices as it enables remote code execution through audio content manipulation. The requirement for user interaction means that exploitation typically occurs when users play malicious audio files, making it particularly concerning for mobile environments where users frequently encounter multimedia content from various sources. Attackers could potentially distribute malicious audio files through various channels including email attachments, messaging applications, or malicious websites, with the payload executing automatically when the audio content is played. The attack vector operates through the standard Android media processing pipeline, making it difficult to detect and prevent without proper input validation mechanisms in place.
The security implications extend beyond simple code execution to include complete system compromise potential, as this vulnerability could allow attackers to gain persistent access to devices without requiring additional privileges. The Android security model relies on proper input validation at multiple layers, and this flaw demonstrates how a single missing bounds check in a multimedia library can create a complete bypass of security controls. Organizations should consider implementing additional runtime protections and monitoring mechanisms to detect potential exploitation attempts. The vulnerability also highlights the importance of regular security updates and patch management processes, as Android 10 users would need to apply security patches to protect against this specific threat vector. Mitigation strategies should include immediate deployment of vendor-provided security patches, implementation of network-based monitoring for suspicious audio content, and user education regarding the dangers of untrusted multimedia files.
This vulnerability aligns with several ATT&CK framework techniques including T1059 for command and scripting interpreter and T1068 for exploit for privilege escalation, as the initial exploitation can lead to broader system compromise. The flaw represents a critical gap in Android's security architecture that demonstrates the need for comprehensive input validation across all multimedia processing components. Security professionals should prioritize this vulnerability for remediation due to its remote exploitability and the low privilege requirements for successful exploitation, making it a high-priority concern for enterprise security teams managing Android device fleets.