CVE-2009-4638 in FFmpeg
Summary
by MITRE
Integer overflow in FFmpeg 0.5 allows remote attackers to cause a denial of service (crash) and possibly execute arbitrary code via unknown vectors.
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Analysis
by VulDB Data Team • 04/30/2026
The vulnerability identified as CVE-2009-4638 represents a critical integer overflow flaw within FFmpeg version 0.5 that exposes systems to both remote denial of service and potential arbitrary code execution attacks. This issue stems from improper handling of integer values during media file processing operations, creating a condition where maliciously crafted input can cause integer wraparound behaviors that lead to unpredictable system states. The vulnerability affects the multimedia processing capabilities of FFmpeg, which serves as a foundational component for numerous applications including web browsers, media players, and content management systems that rely on FFmpeg for video and audio decoding operations.
The technical nature of this integer overflow vulnerability places it within the scope of CWE-190, which specifically addresses integer overflow conditions that can result in buffer overflows, memory corruption, and other exploitable conditions. The flaw manifests when FFmpeg processes media files with specially crafted parameters that cause arithmetic operations to exceed the maximum representable value for integer data types, leading to wraparound behavior that can corrupt memory structures or redirect program execution flow. Attackers can exploit this by crafting malicious media files or stream parameters that trigger the overflow during decoding operations, potentially causing the application to crash or execute unintended code paths.
The operational impact of CVE-2009-4638 extends beyond simple denial of service scenarios, as the vulnerability could potentially enable remote code execution in certain environments where the affected FFmpeg library is used in web-based applications or services. Systems utilizing FFmpeg for processing untrusted media content are particularly at risk, including web applications that accept user-uploaded videos, media streaming services, and content management platforms that rely on FFmpeg for format conversion and playback. The vulnerability's exploitation requires remote access to systems processing media files through FFmpeg, making it especially dangerous for web-facing services and applications that handle user-generated content without proper input validation.
Mitigation strategies for this vulnerability should prioritize immediate patching of FFmpeg installations to versions that address the integer overflow conditions, as recommended by the FFmpeg development team and security advisories from organizations such as the National Vulnerability Database. Organizations should implement comprehensive input validation measures for all media file processing operations, including size and format validation, to prevent exploitation attempts. Additionally, deployment of network segmentation and application firewalls can help limit the attack surface by restricting access to systems that process media content through FFmpeg. The vulnerability also highlights the importance of following secure coding practices such as those outlined in the OWASP Secure Coding Practices and the CERT Secure Coding Standards, particularly regarding integer arithmetic handling and buffer management to prevent similar issues in future implementations.