CVE-2009-4632 in FFmpeg
Summary
by MITRE
oggparsevorbis.c in FFmpeg 0.5 does not properly perform certain pointer arithmetic, which might allow remote attackers to obtain sensitive memory contents and cause a denial of service via a crafted file that triggers an out-of-bounds read.
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Analysis
by VulDB Data Team • 04/30/2026
The vulnerability identified as CVE-2009-4632 resides within the oggparsevorbis.c component of FFmpeg version 0.5, representing a critical memory safety issue that affects multimedia processing applications. This flaw manifests as improper pointer arithmetic during the parsing of Vorbis audio files within the Ogg container format, creating a condition where maliciously crafted audio files can trigger unauthorized memory access patterns. The vulnerability specifically impacts the parsing logic responsible for handling Vorbis codec metadata and audio data structures within Ogg containers, making it particularly dangerous in environments where multimedia content processing is automated or untrusted.
The technical implementation of this vulnerability stems from inadequate bounds checking during pointer manipulation operations within the Vorbis parsing routine. When FFmpeg processes a malformed Ogg file containing crafted Vorbis audio data, the pointer arithmetic calculations fail to validate array indices or memory offsets, resulting in out-of-bounds memory reads. This memory access violation allows attackers to potentially read sensitive data from adjacent memory locations, including stack contents, heap data, or other process memory segments that may contain authentication tokens, cryptographic keys, or other confidential information. The flaw operates at the level of the audio parser, making it particularly insidious as it can be triggered simply by opening or processing a malicious file through any application that relies on FFmpeg for multimedia handling.
From an operational perspective, this vulnerability presents significant risks to both individual users and enterprise environments where multimedia processing is prevalent. Attackers can exploit this issue remotely by delivering malicious Ogg files through various attack vectors including email attachments, web downloads, or media sharing platforms. The impact extends beyond simple information disclosure to include potential denial of service conditions that can crash applications or render systems unstable. The vulnerability's exploitation requires minimal technical expertise, making it attractive to threat actors seeking to compromise systems through low-hanging fruit attacks. Organizations using FFmpeg-based applications for media processing, streaming services, or content management systems face particular exposure as these platforms often process untrusted user-generated content without adequate input sanitization.
Mitigation strategies for CVE-2009-4632 should prioritize immediate software updates to FFmpeg versions that contain fixed pointer arithmetic implementations and enhanced bounds checking mechanisms. System administrators should implement strict file validation procedures for multimedia content processing, including automatic scanning for malformed files and sandboxing of media processing operations. Network security controls such as content filtering and web application firewalls can help prevent the delivery of malicious Ogg files to end-user systems. Additionally, regular security assessments of multimedia processing applications and comprehensive vulnerability scanning should be conducted to identify other potential memory safety issues. The vulnerability aligns with CWE-129, which addresses improper validation of array indices, and maps to ATT&CK technique T1203, which involves exploiting software vulnerabilities for information gathering and system compromise. Organizations should also consider implementing memory protection mechanisms such as stack canaries, address space layout randomization, and control flow integrity checks to further reduce the exploitability of similar memory safety vulnerabilities.