CVE-2016-6765 in Android
Summary
by MITRE
A denial of service vulnerability in libstagefright in Mediaserver could enable an attacker to use a specially crafted file to cause a device hang or reboot. This issue is rated as High due to the possibility of remote denial of service. Product: Android. Versions: 4.4.4, 5.0.2, 5.1.1, 7.0. Android ID: A-31449945.
Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.
Analysis
by VulDB Data Team • 07/20/2020
The vulnerability identified as CVE-2016-6765 represents a critical denial of service flaw within the Android media processing framework, specifically affecting the libstagefright library component that operates within the Mediaserver process. This vulnerability arises from improper handling of malformed media files during the parsing and processing of multimedia content, creating a condition where specially crafted malicious files can trigger system instability. The affected Android versions include 4.4.4, 5.0.2, 5.1.1, and 7.0, indicating this flaw spans multiple major Android releases and affects a substantial portion of the Android ecosystem. The vulnerability is classified as high severity due to its potential for remote exploitation, allowing attackers to compromise device availability without requiring local access or user interaction.
The technical root cause of this vulnerability stems from inadequate input validation and memory management within the stagefright media parser implementation. When the Mediaserver processes media files containing malformed headers, incorrect data structures, or malformed metadata, the parsing logic fails to properly handle these edge cases, leading to buffer overflows, memory corruption, or infinite loops within the processing pipeline. This flaw operates at the system level within the media framework, making it particularly dangerous as it can be triggered through various media file formats including mp4, 3gp, and other supported containers. The vulnerability demonstrates characteristics consistent with CWE-125, which describes out-of-bounds read conditions, and CWE-787, which covers out-of-bounds writes, both of which are common in media processing libraries where buffer boundaries are not properly enforced.
The operational impact of this vulnerability extends beyond simple service disruption, as it can lead to complete device compromise through sustained denial of service attacks. An attacker capable of delivering a malicious media file through email attachments, web downloads, or malicious applications can cause devices to hang indefinitely or reboot repeatedly, effectively rendering them unusable. This attack vector is particularly concerning because it can be executed remotely without user interaction, making it a prime target for automated exploitation campaigns. The vulnerability's exploitation aligns with ATT&CK technique T1489, which covers denial of service attacks, and can be leveraged to create persistent availability issues that may require device reboot or factory reset to resolve. In enterprise environments, this vulnerability could enable attackers to disrupt business operations by targeting employee devices or network infrastructure components that rely on media processing capabilities.
Mitigation strategies for CVE-2016-6765 require immediate patch application through official Android security updates, as Google released comprehensive fixes for this vulnerability in subsequent security bulletins. Organizations should prioritize deployment of Android security patches, particularly for devices running the affected versions, as these updates contain critical fixes for the stagefright media parser logic. Network-level defenses can include media file scanning and filtering mechanisms to prevent potentially malicious media content from reaching end-user devices, though this approach is less effective against remote exploitation scenarios. Device administrators should also implement robust mobile device management policies that enforce automatic security updates and monitor for suspicious media file handling behaviors. The vulnerability highlights the importance of secure coding practices in media processing libraries and demonstrates how seemingly benign file parsing operations can become attack vectors when proper input validation and error handling are not implemented. Additionally, organizations should consider implementing network segmentation and access controls to limit the potential impact of successful exploitation attempts, particularly in environments where media processing capabilities are exposed to untrusted networks or users.