CVE-2019-9308 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-112661742
Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.
Analysis
by VulDB Data Team • 09/12/2020
The vulnerability identified as CVE-2019-9308 resides within the libAACdec component of Android systems, specifically affecting Android 10 deployments. This flaw represents a critical security weakness that stems from improper handling of integer values during audio decoding processes. The vulnerability manifests as an integer overflow condition that can potentially result in out-of-bounds memory writes, creating a pathway for malicious exploitation.
The technical nature of this vulnerability places it squarely within the realm of software security flaws that can be leveraged for remote code execution. The integer overflow occurs during the processing of Advanced Audio Coding audio files, where the decoding library fails to properly validate or constrain integer values used in memory allocation calculations. This flaw allows an attacker to manipulate input data in such a way that arithmetic operations produce values exceeding the maximum representable integer limits, subsequently causing memory corruption in adjacent memory locations.
From an operational perspective, this vulnerability presents a significant risk to Android devices as it requires no additional privileges for exploitation and can be triggered through remote audio content delivery. The requirement for user interaction indicates that a malicious actor would need to convince a victim to play or process a specially crafted audio file, typically through email attachments, web downloads, or malicious applications. This user interaction requirement, while providing some mitigation, does not eliminate the severity of the potential impact. The vulnerability's classification as a remote code execution threat means that successful exploitation could allow attackers to execute arbitrary code on affected devices, potentially leading to complete system compromise.
The implications of this vulnerability extend beyond simple privilege escalation as it represents a serious threat to device integrity and user privacy. Once exploited, an attacker could gain unauthorized access to the device's file system, install malicious applications, access sensitive data, or establish persistent backdoors. The fact that this vulnerability affects the core audio decoding functionality means it could be exploited through numerous legitimate audio playback scenarios, making detection and prevention particularly challenging. The integer overflow and subsequent out-of-bounds write conditions create opportunities for attackers to manipulate program execution flow and potentially overwrite critical system components or memory structures.
Security practitioners should implement immediate mitigations including prompt system updates and patches provided by Google for Android 10 devices. Organizations should also consider network-level monitoring for suspicious audio file downloads and implement application whitelisting policies to restrict audio processing capabilities. The vulnerability aligns with ATT&CK techniques related to privilege escalation and execution through malicious media files, while also mapping to CWE-190 which specifically addresses integer overflow conditions. Regular security assessments and vulnerability scanning should be conducted to ensure all Android devices within organizational networks are properly updated and protected against this and similar audio decoding vulnerabilities that could compromise system integrity and user data security.