CVE-2013-0867 in FFmpeg
Summary
by MITRE
The decode_slice_header function in libavcodec/h264.c in FFmpeg before 1.1.2 does not properly check when the pixel format changes, which allows remote attackers to have unspecified impact via crafted H.264 video data, related to an out-of-bounds array access.
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Analysis
by VulDB Data Team • 05/03/2018
The vulnerability identified as CVE-2013-0867 represents a critical out-of-bounds array access flaw within the FFmpeg multimedia framework's H.264 video decoding implementation. This issue resides in the decode_slice_header function located in libavcodec/h264.c, where the software fails to adequately validate pixel format transitions during video processing. The flaw specifically manifests when handling crafted H.264 video data that manipulates the pixel format parameter in unexpected ways, creating a scenario where array bounds are exceeded during the decoding process. Such vulnerabilities are particularly dangerous because they can be exploited remotely through malicious video content, making them attractive targets for attackers seeking to compromise systems that process multimedia data.
The technical nature of this vulnerability aligns with CWE-129, which addresses improper validation of array index values, and more specifically with CWE-787, which deals with out-of-bounds write operations. The flaw occurs during the H.264 video decoding pipeline where the decoder attempts to process slice headers containing malformed pixel format information. When the pixel format changes unexpectedly during video processing, the decode_slice_header function does not properly validate the new format against the expected array boundaries, leading to memory corruption. This type of vulnerability falls under the ATT&CK technique T1203, where adversaries may leverage software vulnerabilities to execute arbitrary code or cause system instability through media processing applications.
The operational impact of CVE-2013-0867 extends beyond simple memory corruption, as it can result in unspecified consequences that may include arbitrary code execution, system crashes, or information disclosure. Attackers can craft malicious H.264 video files that trigger the out-of-bounds access when processed by vulnerable FFmpeg implementations, potentially affecting any system or application that relies on FFmpeg for video decoding. This includes web browsers, media players, content management systems, and streaming platforms that utilize FFmpeg as their underlying multimedia processing engine. The remote exploitation capability makes this vulnerability particularly concerning for web-based applications where users may unknowingly encounter malicious video content.
Mitigation strategies for CVE-2013-0867 primarily focus on immediate patching of FFmpeg installations to versions 1.1.2 or later, where the pixel format validation has been properly implemented. System administrators should also implement network-level controls to filter potentially malicious video content, particularly in environments where users may encounter untrusted media files. Additionally, organizations should consider implementing sandboxing mechanisms for multimedia processing, which can isolate the effects of potential exploits and prevent them from affecting the broader system. The vulnerability demonstrates the importance of proper input validation in multimedia codecs, as highlighted by industry best practices for secure software development and the principles outlined in the OWASP Top Ten for web application security. Regular security assessments and updates of multimedia processing libraries remain essential for maintaining system integrity against similar vulnerabilities that may arise from complex codec implementations.