CVE-2019-2159

Vulnerability

In libxaac, a media codec library on Android 10 (version 2019-09-01 patch level), there is a possible out-of-bounds write due to a missing bounds check. This vulnerability, assigned CVE-2019-2159, is present in devices running Android 10 with a security patch level before 2019-09-01. The issue requires user interaction, specifically opening a malicious media file, to reach the affected code path [1].

Exploitation

An attacker can exploit this vulnerability by crafting a specially prepared media file that, when processed by the vulnerable libxaac codec, triggers an out-of-bounds write. The attacker does not need any additional execution privileges; the exploit path is triggered when a user opens the malicious file in an application that uses the affected library, such as a media player or messaging app. No network position or authentication is required beyond delivering the file to the user [1].

Impact

Successful exploitation leads to remote code execution within the context of the application processing the media file. The attacker can achieve arbitrary write operations, potentially gaining the ability to execute arbitrary code with the privileges of the media service, which may include access to sensitive data or further system compromise. The CIA impact is high, as it enables full compromise of the application's process [1].

Mitigation

This vulnerability is addressed as part of the Android 10 release, which includes a security patch level of 2019-09-01. Devices with this patch level or later are protected. Users should ensure their device's security patch level is at least 2019-09-01 by updating to the latest Android 10 build. No workarounds are available for devices that cannot receive updates. The Android security bulletin provides the source code patches as part of the AOSP release [1].