CVE-2015-3831 in Android
Summary
by MITRE
Buffer overflow in the readAt function in BpMediaHTTPConnection in media/libmedia/IMediaHTTPConnection.cpp in the mediaserver service in Android before 5.1.1 LMY48I allows attackers to execute arbitrary code via a crafted application, aka internal bug 19400722.
If you want to get the best quality for vulnerability data then you always have to consider VulDB.
Analysis
by VulDB Data Team • 02/03/2018
The vulnerability described in CVE-2015-3831 represents a critical buffer overflow flaw within the Android mediaserver service that affects versions prior to 5.1.1 LMY48I. This vulnerability exists in the BpMediaHTTPConnection component, specifically within the readAt function located in media/libmedia/IMediaHTTPConnection.cpp. The mediaserver service operates as a privileged system component responsible for handling multimedia operations including audio and video playback, streaming, and media file processing. When a malicious application attempts to read media content through this interface, the buffer overflow condition can be triggered, potentially allowing remote code execution.
The technical nature of this vulnerability stems from improper bounds checking within the readAt function implementation. When processing data streams from HTTP connections, the function fails to validate the size of incoming data against allocated buffer boundaries, creating a condition where attacker-controlled data can overwrite adjacent memory regions. This type of flaw falls under CWE-121, which describes stack-based buffer overflow conditions, and specifically relates to CWE-787, which addresses out-of-bounds write operations. The vulnerability allows an attacker to manipulate memory layout and potentially overwrite critical function pointers or return addresses, leading to arbitrary code execution with the privileges of the mediaserver process.
The operational impact of this vulnerability is significant as it provides attackers with a means to execute arbitrary code on affected Android devices without requiring physical access or user interaction beyond installing a malicious application. The mediaserver service runs with elevated privileges and has access to various system resources, making successful exploitation particularly dangerous. Attackers could leverage this vulnerability to install persistent backdoors, access sensitive user data, or escalate privileges to gain full system control. The vulnerability affects the core multimedia framework, meaning any application that utilizes HTTP-based media streaming or downloads could potentially serve as an attack vector, making it a widespread concern across the Android ecosystem.
Mitigation strategies for this vulnerability include immediate deployment of the security patch released by Google as part of Android 5.1.1 LMY48I update cycle. Organizations should prioritize updating all affected devices to the latest Android version that contains the fix. Additionally, implementing network-level restrictions such as firewall rules that limit HTTP traffic to trusted sources can reduce attack surface. The vulnerability demonstrates the importance of input validation and memory safety practices in system components that handle external data streams, aligning with ATT&CK technique T1059.007 for command and scripting interpreter usage. Security teams should also consider implementing application sandboxing and monitoring for unusual network activity patterns that might indicate exploitation attempts. Regular security assessments of media handling components and adherence to secure coding practices including bounds checking and memory management are essential for preventing similar vulnerabilities in future implementations.