CVE-2019-9297 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-112890242
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Analysis
by VulDB Data Team • 09/12/2020
The vulnerability identified as CVE-2019-9297 resides within the libAACdec component of Android's media framework, specifically affecting the Advanced Audio Coding audio decoding library. This flaw represents a critical security issue that demonstrates the complex interplay between audio codec processing and memory safety mechanisms in mobile operating systems. The vulnerability manifests as an integer overflow condition that occurs during the processing of malformed audio data, creating a potential pathway for malicious actors to execute arbitrary code on affected devices.
The technical root cause of this vulnerability stems from improper handling of integer values during audio frame parsing operations. When libAACdec processes specially crafted audio files, the decoder fails to properly validate the size parameters of audio frames, leading to an integer overflow condition. This overflow results in an out-of-bounds memory write operation where the decoder attempts to write data beyond the allocated memory boundaries. The flaw is particularly dangerous because it can be triggered through audio files that appear legitimate to the system but contain maliciously constructed data structures. The integer overflow occurs during the calculation of buffer sizes or frame dimensions, where the computation exceeds the maximum representable value for the integer type, causing the subsequent memory allocation to be insufficient for the actual data processing requirements.
The operational impact of this vulnerability extends beyond simple code execution capabilities to encompass significant security implications for Android users. Remote code execution potential means that attackers can compromise devices through malicious audio content delivered via various channels including email attachments, web downloads, or media streaming services. The requirement for user interaction indicates that exploitation typically occurs when users play or open audio files, making this vulnerability particularly insidious as it leverages normal user behavior to achieve compromise. This vulnerability affects Android 10 and earlier versions, representing a substantial attack surface across numerous devices and applications that rely on the affected media processing libraries. The lack of additional execution privileges required for exploitation makes this vulnerability particularly dangerous as it can be exploited without requiring users to grant special permissions or elevate their privileges.
Security researchers have classified this vulnerability under CWE-190, which specifically addresses integer overflow conditions, and it aligns with ATT&CK technique T1059.007 for execution through audio processing components. The vulnerability demonstrates how multimedia processing libraries can serve as attack vectors in modern mobile operating systems, where seemingly benign functionality can be weaponized for system compromise. Mitigation strategies should focus on immediate patching of affected Android versions, implementing robust input validation for audio processing components, and deploying network-level protections to filter potentially malicious audio content. Organizations should also consider implementing application sandboxing measures and monitoring for unusual audio processing activities that might indicate exploitation attempts. The vulnerability highlights the importance of thorough security testing for multimedia components and the need for continuous vulnerability assessment of system libraries that handle untrusted input data.