CVE-2021-30123 Memory corruption in n/a
A buffer overflow in FFmpeg allows remote code execution via a crafted file, requiring users to upgrade to a patched version.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2021-30123?
CVE-2021-30123 is a high-severity memory corruption vulnerability in Ffmpeg Ffmpeg, published on 7 Apr 2021. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Official description
FFmpeg <=4.3 contains a buffer overflow vulnerability in libavcodec through a crafted file that may lead to remote code execution.
Weakness: CWE-120
Which versions are affected by CVE-2021-30123?
It affects 1 product.
Products include Ffmpeg Ffmpeg.
How do I fix CVE-2021-30123?
Upgrade to a fixed version.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2021-30123 being exploited?
There is no known exploitation of CVE-2021-30123 in the wild and no public exploit code.
Other vulnerabilities in Ffmpeg Ffmpeg
Sources
Also known as CLEANSTART-2024-LL28632, GHSA-gx3h-4rx7-q328, JLSEC-2025-112.