CVE-2019-2149 in Android
Summary
by MITRE
In libxaac, there is a possible out of bounds read due to a missing bounds check. This could lead to information disclosure with no additional execution privileges needed. User interaction is needed for exploitation. Product: AndroidVersions: Android-10Android ID: A-113262406
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Analysis
by VulDB Data Team • 09/11/2020
The vulnerability identified as CVE-2019-2149 resides within the libxaac library component of Android systems, specifically affecting Android 10 installations. This issue represents a classic out-of-bounds read condition that occurs when the system fails to validate input data boundaries before processing audio content. The flaw manifests in the Advanced Audio Coding (AAC) decoding functionality where insufficient bounds checking allows maliciously crafted audio files to trigger memory access violations. According to the Android security advisory A-113262406, this vulnerability requires user interaction for exploitation, meaning an attacker must convince a victim to open or play a specially crafted audio file to initiate the attack vector. The vulnerability is categorized under CWE-129, which specifically addresses insufficient bounds checking in software implementations, making it a well-documented class of memory safety issues that frequently leads to information disclosure and potential system compromise.
The technical execution of this vulnerability involves the manipulation of AAC audio files that contain malformed data structures within their metadata or audio payload sections. When the libxaac library processes these malicious inputs without proper validation, the decoder attempts to read memory locations beyond the allocated buffer boundaries. This out-of-bounds memory access can result in the disclosure of sensitive information stored in adjacent memory regions, including cryptographic keys, session tokens, or other confidential data that may be resident in the process memory space. The exploitation does not require elevated privileges or root access, as the vulnerability exists within a user-space component that handles standard audio processing tasks. The Android security model considers this a medium severity issue because while it does not enable arbitrary code execution, the information disclosure aspect can provide attackers with valuable data that may be used in subsequent attack phases.
From an operational perspective, this vulnerability impacts Android 10 devices and potentially earlier versions that utilize the affected libxaac library for audio processing. The attack surface is broad as any application that processes audio files, including media players, messaging applications, and web browsers, could be exploited through this vector. The requirement for user interaction means that social engineering tactics become crucial for successful exploitation, as attackers must convince users to open malicious content. Security professionals should note that this vulnerability aligns with ATT&CK technique T1059.007, which involves the use of audio and video files as attack vectors, and T1068, which covers the exploitation of remote services through user interaction. The information disclosure aspect makes this particularly concerning for applications handling sensitive content or those operating in environments where privacy is paramount.
Mitigation strategies for CVE-2019-2149 should focus on both immediate patching and operational security measures. Android device manufacturers and carriers should prioritize the deployment of security updates that contain fixed versions of the libxaac library, as these updates address the missing bounds checking logic. Users should ensure their devices are running the latest security patches, particularly those released after the vulnerability disclosure. Network security teams can implement content filtering measures to block suspicious audio file types and monitor for unusual audio processing activities that might indicate exploitation attempts. Additionally, organizations should consider implementing application whitelisting policies that restrict the execution of untrusted audio files and establish robust incident response procedures for detecting potential information disclosure events. The vulnerability serves as a reminder of the importance of memory safety practices in multimedia processing libraries and underscores the need for comprehensive input validation across all system components that handle user-provided data.