Ffmpeg has an exceptionally terrible track record when it comes to security. People have been throwing fuzzers at it for as long as I remember and coming back with a nearly inexhaustible supply of memory corruption bugs. Here's an effort by one Googler a decade ago:
So, while it's a demo of the capabilities of LLMs, this should not be at all surprising. Ffmpeg is absolutely not something you should be running outside of a sandbox if you're touching any untrusted or user-supplied content. I know that people do, and these people are taking unreasonable risks.
zerobees
I think the industry is optimizing for the wrong thing. Generating thousands of AI-written bug reports is easy, at least with Mythos (preview 1) or GPT-5.5. Getting bugs fixed is the hard part.
A few months ago I started working on a system that finds critical security issues and opens PRs instead of just filing reports. The acceptance rate is sitting at roughly 94% so far. Most of the failures were due to project-specific kill switches or other internal mechanisms that weren’t documented, not because the vulnerability itself was misidentified.
Developers generally seem to prefer this approach. A bug report creates work. A good PR removes work. That sounds obvious, but a lot of security products still stop at the report and call it a day.
guessmyname
>The reach of this bug is what makes it serious. Any deployment that points FFmpeg at an attacker-influenced RTSP URL is exposed: media ingest pipelines fetching user-supplied stream URLs, surveillance and CCTV systems pulling RTSP feeds, and transcoding services processing remote AV1-over-RTP sources
Wow this is actually pretty serious - I'm even surprised its being published. There are several services where I can imagine this is exploitable today.
nemothekid
Even if this isn't as big a deal as this [advertisement for a security company] seems, it is a reminder that every application you release does have a security hole somewhere, and a script kiddie can now find it 5 minutes after release for $2 in credit. If you're not red-teaming your code before release, hackers are doing it after.
0xbadcafebee
Inflated use of the term zero-day, while none of the described vulnerabilities is actually a zero-day. But it sounds and clicks good..
thank you for the PoC.
lschueller
That's not what "zero-day" means.
da_chicken
> At this point the corrupted free pointer is called, and control of the instruction pointer is ours.
Very serious, though in practice it doesn't sound like this bug achieves arbitrary RCE on its own (especially in the presence of ASLR). You would need there to be some writable and executable page of memory lying around.
wavemode
I've been using ffmpeg for a very long time, both personally and for services I've built. Fabrice Bellard is a genius, and the developers who have taken it so far have made the world measurably richer.
But I can't think of a program more worthy of sandboxing when run with untrusted input than ffmpeg. It's a huge amount of C dealing with the most complicated video and audio codecs, which is notoriously impossible to get completely right.
But it's not actually that big of a problem. I run ffmpeg inside a VM or gVisor, and the end result is usually a video file that I'm perfectly willing to play in my browser, where it gets decoded in yet another sandbox because this shit is hard.
jacobgold
The incentives structure is deeply broken in the field of Security Research.
They are the middle management of the FOSS world.
Celebrated for dumping more work on volunteers. The more urgent the work, the more they are celebrated. Acknowledging the realistic impact of issues or the pragmatic implications of an issue are at odds with their incentives.
It's hard not to see them as bottom feeders of the software industry and I wish we would starting treating them like pariah. Submit the PR or STFU.
techscruggs
Is the future of defense-against-foreign-agents-on-my-codebase to subtly hide prompt injections into one’s codebase that would defeat agents to find security bugs ?
If the attackers of ffmpeg need to be using such those authors’ services to find RCE in popular tools to attack, what the ffmpeg team needs to defeat attackers is to reduce efficiency of such tools depthfirst
comments (10)
https://security.googleblog.com/2014/01/ffmpeg-and-thousand-...
So, while it's a demo of the capabilities of LLMs, this should not be at all surprising. Ffmpeg is absolutely not something you should be running outside of a sandbox if you're touching any untrusted or user-supplied content. I know that people do, and these people are taking unreasonable risks.
zerobees
A few months ago I started working on a system that finds critical security issues and opens PRs instead of just filing reports. The acceptance rate is sitting at roughly 94% so far. Most of the failures were due to project-specific kill switches or other internal mechanisms that weren’t documented, not because the vulnerability itself was misidentified.
Developers generally seem to prefer this approach. A bug report creates work. A good PR removes work. That sounds obvious, but a lot of security products still stop at the report and call it a day.
guessmyname
Wow this is actually pretty serious - I'm even surprised its being published. There are several services where I can imagine this is exploitable today.
nemothekid
0xbadcafebee
lschueller
da_chicken
Very serious, though in practice it doesn't sound like this bug achieves arbitrary RCE on its own (especially in the presence of ASLR). You would need there to be some writable and executable page of memory lying around.
wavemode
But I can't think of a program more worthy of sandboxing when run with untrusted input than ffmpeg. It's a huge amount of C dealing with the most complicated video and audio codecs, which is notoriously impossible to get completely right.
But it's not actually that big of a problem. I run ffmpeg inside a VM or gVisor, and the end result is usually a video file that I'm perfectly willing to play in my browser, where it gets decoded in yet another sandbox because this shit is hard.
jacobgold
It's hard not to see them as bottom feeders of the software industry and I wish we would starting treating them like pariah. Submit the PR or STFU.
techscruggs
If the attackers of ffmpeg need to be using such those authors’ services to find RCE in popular tools to attack, what the ffmpeg team needs to defeat attackers is to reduce efficiency of such tools depthfirst
ttoinou