CVE-2023-51797

What it actually does

Buffer overflow in showwaves_filter_frame at libavfilter/avf_showwaves.c:722 allows a local attacker to execute arbitrary code by supplying crafted input to the FFmpeg showwaves filter.

Why it matters to the business

Local compromise of media-processing systems can lead to unauthorized code execution, data theft, or disruption of video and audio workflows on affected hosts.

How an attack unfolds

An attacker with local access crafts a malicious media file that triggers the overflow when the showwaves filter processes it, resulting in arbitrary code execution within the FFmpeg process.

How to fix it

Upgrade FFmpeg to a version that contains the fix for the buffer overflow in avf_showwaves.c; rebuild any downstream packages that statically link the vulnerable libavfilter.

How to confirm the fix worked

Confirm the installed FFmpeg version is newer than the vulnerable release, recompile with the patch applied, and test processing of known trigger inputs to verify the overflow no longer occurs.

Typical attack path

1. Locate a vulnerable FFmpeg binary on the target system
2. Prepare a specially crafted input file that exercises the showwaves filter path
3. Invoke FFmpeg locally with the showwaves filter on the malicious file
4. Achieve arbitrary code execution in the context of the FFmpeg process

How to detect it

Review system and application logs for FFmpeg crashes or unexpected exits when the showwaves filter is invoked; correlate with file-access timestamps on media processed by the filter.

What your security team should do

• Apply the latest FFmpeg security updates as soon as they become available
• Run FFmpeg inside containers or sandboxes to limit the impact of local code execution
• Restrict untrusted local users from invoking FFmpeg on arbitrary media files
• Monitor upstream FFmpeg commits and security advisories for the specific showwaves fix