CVE-2019-9301 in Android
Summary
by MITRE
In libAACdec, there is a possible out of bounds write due to an integer overflow. 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-112663384
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Analysis
by VulDB Data Team • 09/12/2020
The vulnerability identified as CVE-2019-9301 resides within the libAACdec component of Android's media framework, specifically affecting the Advanced Audio Coding audio decoding functionality. This issue represents a critical security flaw that demonstrates how seemingly benign audio processing operations can be weaponized for system compromise. The vulnerability manifests as an integer overflow condition that occurs during the parsing of AAC audio frames, where the decoder fails to properly validate input parameters before performing memory allocation operations.
The technical flaw stems from an insufficient bounds check within the audio decoding logic where integer overflow conditions allow maliciously crafted audio data to bypass normal input validation mechanisms. When processing specially constructed AAC files, the decoder's internal counters or size calculations can overflow, leading to incorrect memory allocation sizes that subsequently result in out-of-bounds write operations. This vulnerability falls under CWE-190, which specifically addresses integer overflow conditions, and represents a classic example of how integer arithmetic errors can translate into memory corruption vulnerabilities. The flaw operates at the intersection of audio codec processing and memory management, where the decoder's failure to properly handle edge cases in frame size calculations creates exploitable conditions.
The operational impact of this vulnerability extends beyond simple audio processing failures, as it enables remote code execution capabilities without requiring any special privileges or user-level access. An attacker can craft malicious AAC audio files that, when played through an affected Android device, will trigger the integer overflow condition and subsequently overwrite adjacent memory locations. The requirement for user interaction means that exploitation typically occurs through social engineering tactics where users are tricked into playing malicious audio content, though this interaction requirement does not significantly reduce the threat level given the ease of delivery through various channels including email attachments, web downloads, or instant messaging applications. This vulnerability directly maps to attack techniques described in the ATT&CK framework under T1059 for command and scripting interpreter and T1068 for exploit for privilege escalation, as it provides a pathway for initial compromise that can lead to further system exploitation.
The implications of this vulnerability are particularly severe in mobile environments where users frequently interact with multimedia content from untrusted sources, and the lack of additional execution privileges required for exploitation makes it accessible to threat actors with minimal technical expertise. Android 10 represents the primary affected version, though other versions may also be vulnerable depending on their implementation of the libAACdec library. The vulnerability's classification as a remote code execution threat means that attackers can potentially gain full control over affected devices, enabling them to install malicious applications, access sensitive user data, or establish persistent backdoors. Organizations and users should prioritize updating their Android systems to versions that contain patches addressing this specific integer overflow condition, as the vulnerability represents a significant risk to mobile device security and privacy.