CVE-2014-9628 in VLC Media Player
Summary
by MITRE
The MP4_ReadBox_String function in modules/demux/mp4/libmp4.c in VideoLAN VLC media player before 2.1.6 allows remote attackers to trigger an unintended zero-size malloc and conduct buffer overflow attacks, and consequently execute arbitrary code, via a box size of 7.
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Analysis
by VulDB Data Team • 03/08/2022
The vulnerability identified as CVE-2014-9628 represents a critical memory corruption flaw within the VideoLAN VLC media player software ecosystem. This issue resides in the MP4_ReadBox_String function located in the modules/demux/mp4/libmp4.c source file, which forms part of VLC's multimedia processing pipeline for handling mp4 container format files. The flaw manifests when the application processes malformed mp4 boxes with a specific size parameter of seven bytes, creating a dangerous condition that can be exploited by remote attackers to execute arbitrary code on vulnerable systems. The vulnerability operates at the intersection of memory management and input validation, making it particularly dangerous as it can be triggered through network-based attacks without requiring user interaction.
The technical exploitation mechanism involves a specific memory allocation pattern that leads to a zero-size malloc operation, followed by subsequent buffer overflow conditions. When the MP4_ReadBox_String function encounters a box with a size of seven bytes, it calculates memory requirements based on malformed input data, resulting in a malloc call with zero bytes allocated. This zero-size allocation often results in undefined behavior within the memory allocator, potentially creating heap corruption conditions that attackers can manipulate. The subsequent buffer overflow occurs when the application attempts to write data beyond the allocated memory boundaries, effectively allowing attackers to overwrite adjacent memory regions and potentially control program execution flow. This vulnerability directly maps to CWE-122, which describes heap-based buffer overflow conditions, and CWE-787, which covers out-of-bounds write vulnerabilities.
The operational impact of CVE-2014-9628 extends far beyond simple remote code execution capabilities, as it represents a sophisticated attack vector that can be leveraged across multiple threat scenarios. Attackers can utilize this vulnerability to deliver malicious payloads through crafted mp4 files that appear legitimate to users, making the attack surface particularly broad within media consumption environments. The vulnerability affects VLC versions prior to 2.1.6, meaning any system running these older versions remains at risk when processing mp4 content from untrusted sources. The attack can be executed remotely through various delivery mechanisms including web downloads, email attachments, or streaming services, making it a significant concern for organizations and individual users alike. The vulnerability also aligns with ATT&CK technique T1059, which covers command and scripting interpreter usage, as successful exploitation can lead to full system compromise and persistent access.
Mitigation strategies for this vulnerability primarily focus on immediate software updates and patch management procedures. Organizations should prioritize upgrading to VLC version 2.1.6 or later, which contains the necessary code modifications to properly validate box sizes and prevent the zero-size malloc condition. Additional defensive measures include implementing network-based filtering rules that block mp4 content from untrusted sources, deploying sandboxing solutions for media processing, and establishing robust input validation procedures for multimedia files. The vulnerability highlights the importance of proper memory management practices and input validation in multimedia processing libraries, as it demonstrates how seemingly benign parameter values can lead to catastrophic memory corruption. Security teams should also consider implementing automated vulnerability scanning tools that can detect the presence of vulnerable VLC versions in their environments, and establish monitoring procedures to identify potential exploitation attempts through network traffic analysis. The remediation process should include comprehensive testing of patched versions to ensure that legitimate functionality remains intact while eliminating the memory corruption vulnerability.