CVE-2016-6722 in Android
Summary
by MITRE
An information disclosure vulnerability in libstagefright in Mediaserver in Android 4.x before 4.4.4, 5.0.x before 5.0.2, 5.1.x before 5.1.1, 6.x before 2016-11-01, and 7.0 before 2016-11-01 could enable a local malicious application to access data outside of its permission levels. This issue is rated as Moderate because it could be used to access sensitive data without permission. Android ID: A-31091777.
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Analysis
by VulDB Data Team • 09/30/2022
The CVE-2016-6722 vulnerability represents a critical information disclosure flaw within the libstagefright media processing library that forms the core of Android's Mediaserver component. This vulnerability exists in multiple Android versions including 4.x before 4.4.4, 5.0.x before 5.0.2, 5.1.x before 5.1.1, 6.x before 2016-11-01, and 7.0 before 2016-11-01, making it one of the most widespread media processing vulnerabilities in Android history. The flaw stems from improper memory handling within the stagefright media framework that processes multimedia content, creating a pathway for unauthorized data access that bypasses normal Android permission boundaries.
The technical root cause of this vulnerability lies in a buffer overflow condition that occurs when processing malformed media files within the libstagefright library. When the Mediaserver processes specially crafted media content, it fails to properly validate input data, leading to memory corruption that can be exploited to read beyond allocated memory boundaries. This allows a malicious application with minimal privileges to access sensitive data that should normally be restricted to higher-privilege processes or system components. The vulnerability is particularly concerning because it operates at the system level within the Mediaserver process, which runs with elevated privileges and has access to various system resources and data stores.
The operational impact of CVE-2016-6722 extends beyond simple data disclosure, as it represents a significant privilege escalation vector that could enable attackers to access sensitive system information, user data, and potentially system credentials. The vulnerability's classification as Moderate severity belies its potential for serious consequences since it allows local malicious applications to bypass normal Android security models and access data outside their intended permission levels. Attackers could leverage this vulnerability to extract personal information, access communication data, or potentially gain deeper system access that could lead to complete device compromise. The widespread nature of affected Android versions means that a substantial portion of the Android ecosystem was vulnerable to this attack vector.
Security researchers have mapped this vulnerability to CWE-125, which describes "Out-of-bounds Read" conditions in software implementations, and it aligns with ATT&CK technique T1059.007 for "Command and Scripting Interpreter: JavaScript" in scenarios where media processing is exploited through web-based or application-based attack vectors. The vulnerability demonstrates how media processing libraries can serve as attack surfaces for privilege escalation and data exfiltration. Mitigation strategies include applying the relevant Android security patches released by Google, implementing proper input validation for media content, and utilizing application sandboxing techniques to limit the potential impact of such vulnerabilities. Organizations should also consider network-level monitoring for suspicious media file processing activities and maintain updated threat intelligence regarding similar vulnerabilities in media processing frameworks.