CVE-2019-9405 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-112890225
Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.
Analysis
by VulDB Data Team • 09/13/2020
The vulnerability CVE-2019-9405 affects the libAACdec component within Android's media framework, specifically targeting the Advanced Audio Coding audio decoder. This issue represents a critical security flaw that resides in the audio processing pipeline of Android 10 systems. The vulnerability manifests as an integer overflow condition that can potentially result in an out-of-bounds write operation, creating a significant attack surface for malicious actors seeking to compromise Android devices.
The technical flaw occurs within the AAC audio decoding logic where integer overflow conditions lead to improper buffer size calculations. When processing maliciously crafted audio files, the decoder fails to properly validate input parameters, allowing an attacker to manipulate the integer arithmetic in such a way that subsequent memory operations exceed allocated buffer boundaries. This type of vulnerability falls under the CWE-190 category of Integer Overflow or Wraparound, which is classified as a fundamental weakness in software design that can lead to memory corruption and arbitrary code execution.
The operational impact of this vulnerability is severe as it enables remote code execution without requiring any special privileges or user permissions to be granted. Attackers can exploit this flaw by delivering malicious audio content through various channels including email attachments, web downloads, or streaming services. The requirement for user interaction suggests that the exploit must be triggered by the user opening or playing the malicious file, but once executed, the attacker gains full control over the affected device. This aligns with ATT&CK technique T1059.007 for Command and Scripting Interpreter and T1543.003 for Create or Modify System Process, as the successful exploitation would allow for persistent access and system control.
The vulnerability affects Android 10 systems specifically, making it particularly concerning given the widespread adoption of this Android version. The Android ID A-112890225 indicates this was properly tracked and addressed by Google's security team. The integer overflow condition in libAACdec represents a classic memory safety issue that demonstrates the importance of proper input validation and boundary checking in multimedia processing libraries. This flaw underscores the critical need for robust security testing of media codecs, which are frequently targeted by attackers due to their complex processing requirements and the potential for remote exploitation through media files.
Mitigation strategies should include immediate installation of the relevant Android security patches released by Google, which would address the integer overflow condition in the AAC decoder. System administrators and users should also implement additional protective measures such as disabling automatic media playback, using updated antivirus solutions, and avoiding untrusted audio content sources. The vulnerability highlights the necessity of regular security updates and the importance of maintaining secure coding practices in multimedia processing components, particularly those handling user-supplied content. Organizations should also consider network-level filtering of suspicious audio content and implement monitoring solutions to detect potential exploitation attempts targeting similar media processing vulnerabilities.