CVE-2019-2055 in Android
Summary
by MITRE
In libxaac, there is a possible out of bounds write due to a missing bounds check. 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-113164693
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Analysis
by VulDB Data Team • 09/11/2020
The vulnerability identified as CVE-2019-2055 resides within the libxaac library component of Android systems, specifically affecting Android 10 installations. This flaw represents a critical security weakness that stems from inadequate input validation mechanisms within the audio processing framework. The issue manifests as a potential out of bounds write condition that occurs when the library fails to properly validate input data boundaries during audio decoding operations. The vulnerability is classified under CWE-129 as an insufficient boundary check, which directly enables memory corruption scenarios that can be exploited by malicious actors.
The technical implementation of this vulnerability involves the libxaac library's handling of audio frame data where insufficient validation occurs before memory allocation and data writing operations. When processing specially crafted audio content, the library does not perform adequate bounds checking on array indices or buffer sizes, allowing an attacker to write data beyond the allocated memory boundaries. This memory corruption can potentially overwrite critical program structures, function pointers, or return addresses within the application's memory space, creating opportunities for arbitrary code execution.
Remote code execution capabilities arise from the fact that this vulnerability can be triggered through network-based audio content delivery without requiring any special privileges or user interaction beyond the initial content consumption. The Android operating system's multimedia framework processes audio files through libxaac without sufficient input sanitization, making it susceptible to exploitation. The attack vector typically involves delivery of maliciously formatted audio files through various channels including email attachments, web downloads, or streaming services that utilize the affected library. This makes the vulnerability particularly dangerous as it can be exploited in passive attack scenarios where users simply need to access or play the malicious content.
The operational impact of CVE-2019-2055 extends beyond simple code execution to potentially compromise entire device systems, as the affected library operates within the core multimedia processing pathways of Android. Attackers can leverage this vulnerability to execute arbitrary code with the privileges of the affected application process, potentially escalating to system-level access depending on the specific implementation details. The vulnerability's exploitation requires minimal user interaction, typically limited to opening or playing the malicious content, which significantly increases the attack surface and potential for widespread compromise. The Android ID A-113164693 indicates this was tracked as a significant security concern within Google's internal vulnerability tracking system, highlighting its severity and the need for immediate remediation.
Mitigation strategies for this vulnerability primarily involve applying the latest security patches provided by Google and device manufacturers, as the fix typically involves implementing proper bounds checking mechanisms within the libxaac library. Organizations should prioritize immediate deployment of Android security updates that address this specific memory corruption issue, particularly in environments where users may be exposed to untrusted audio content. Additionally, network-level filtering of audio content and user education regarding safe content consumption practices can provide additional defense layers. The vulnerability demonstrates the importance of proper input validation in multimedia libraries and aligns with ATT&CK technique T1059.007 for process injection and T1203 for exploitation for execution, as attackers can leverage memory corruption to gain unauthorized code execution capabilities within the target system.