CVE-2016-3941 in VLC Media Player
Summary
by MITRE
Buffer overflow in the AStreamPeekStream function in input/stream.c in VideoLAN VLC media player before 2.2.0 allows remote attackers to cause a denial of service (crash) via a crafted wav file, related to "seek across EOF."
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Analysis
by VulDB Data Team • 05/06/2019
The vulnerability CVE-2016-3941 represents a critical buffer overflow condition within the VideoLAN VLC media player software, specifically affecting versions prior to 2.2.0. This flaw exists in the AStreamPeekStream function located in the input/stream.c source file, demonstrating a classic software security weakness that can be exploited remotely to disrupt system operations. The vulnerability manifests when the media player processes specially crafted wav files that trigger improper handling of stream seeking operations beyond end-of-file boundaries.
The technical exploitation of this vulnerability occurs through a specific sequence of operations where the AStreamPeekStream function fails to properly validate buffer boundaries when attempting to seek across end-of-file positions. This improper boundary checking creates a scenario where an attacker can construct a malicious wav file that, when processed by the vulnerable VLC version, causes the application to write beyond allocated memory buffers. The flaw directly relates to CWE-121, which describes stack-based buffer overflow conditions, and CWE-122, which covers heap-based buffer overflow scenarios. The attack vector operates entirely through network-based delivery of the malicious media file, requiring no local privileges or user interaction beyond opening the file.
The operational impact of this vulnerability extends beyond simple denial of service to potentially enable more sophisticated attacks depending on the execution environment. When exploited, the buffer overflow causes the VLC media player to crash and terminate unexpectedly, effectively rendering the application unavailable for legitimate media playback operations. This crash condition can be particularly disruptive in automated systems or environments where VLC is used as a media processing component. The vulnerability's remote exploitability means that attackers can trigger the condition without physical access to the target system, making it a significant concern for networked environments and web-based media delivery systems.
Security practitioners should note that this vulnerability aligns with ATT&CK technique T1203, which covers exploitation of remote services through buffer overflow conditions, and T1499, which covers network disruption through service availability attacks. The flaw demonstrates how multimedia processing applications can become attack vectors when proper input validation and memory management practices are not implemented. Organizations using VLC media player should immediately implement patch management protocols to upgrade to version 2.2.0 or later, which contains the necessary fixes to prevent the buffer overflow condition. Additionally, network administrators should consider implementing file type validation and content filtering measures to prevent potentially malicious media files from reaching end-user systems, particularly in environments where VLC is used for automated media processing or streaming applications.