CVE-2023-51795

What it actually does

Local buffer overflow in libavfilter/avf_showspectrum.c showspectrumpic_request_frame allows an attacker to overwrite memory and execute arbitrary code.

Why it matters to the business

An attacker with local access can run malicious code on systems that process media with FFmpeg, potentially leading to unauthorized access or system takeover.

How an attack unfolds

An attacker supplies a specially crafted input file or stream that exercises the showspectrumpic filter; the malformed data triggers an out-of-bounds write in showspectrumpic_request_frame, allowing control of the instruction pointer and execution of attacker-supplied code.

How to fix it

Upgrade FFmpeg to a version that contains the fix for the buffer overflow in showspectrumpic_request_frame; rebuild any dependent applications against the patched library and verify the vulnerable code path is no longer reachable.

How to confirm the fix worked

Confirm the installed FFmpeg version is newer than the affected build, review build logs or source for the corrected avf_showspectrum.c, and test that the showspectrumpic filter no longer crashes or allows memory corruption on malformed input.

Typical attack path

1. Identify a target system that invokes FFmpeg with the showspectrumpic filter
2. Craft a malicious media file that reaches the vulnerable code path at line 1789
3. Trigger processing of the file via local execution or an application that calls FFmpeg
4. Overwrite adjacent memory to hijack control flow and execute arbitrary code

How to detect it

Review local process execution logs and application audit trails for FFmpeg invocations that reference showspectrumpic; look for unusual crashes or memory corruption indicators in media-processing workflows.

What your security team should do

• Prioritize patching FFmpeg on all systems that process untrusted media
• Restrict local execution of FFmpeg to trusted users and inputs until patched
• Monitor for new fixed releases and update build pipelines accordingly