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104 points trollied | 3 comments | | HN request time: 0s | source
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vqtska ◴[] No.45785720[source]
I wonder if this vulnerable codec is enabled by default when building FFmpeg? Because if so, then it doesn't matter that it's a "1990s game codec" because any application using FFmpeg to accept arbitrary video files is vulnerable to memory corruption, which should probably be taken more seriously.
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IshKebab ◴[] No.45786093[source]
I checked with Ubuntu's ffmpeg and it is enabled by default. There are a huge list of codecs enabled by default (maybe all of them?). Given the security track record of codecs implemented in C, this means it's basically guaranteed that there are dozens of security vulnerabilities in ffmpeg.

I think the same is probably true for VLC to a lesser extent, which is pretty wild considering I've never heard of it being used as an attack vector, e.g. via torrents.

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haskellshill ◴[] No.45786299[source]
VLC is pretty popular on windows, but ffmpeg? Is there any commonly used windows app that relies on it? I doubt it'd be worth one's time to write exploits for desktop linux
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dpe82 ◴[] No.45788108[source]
VLC and ffmpeg share the same underlying library family (libav*) where this vulnerability lives.

> I doubt it'd be worth one's time to write exploits for desktop Linux

How many developers, network administrators, etc. run desktop Linux? Gaining access to those can be very, very valuable.

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brigade ◴[] No.45788198[source]
FFmpeg based players have been popular for 20 years now. Has there been a single documented actual use of their libraries as the exploitation vector anytime in the last two decades?
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dpe82 ◴[] No.45788461[source]
I'm certain it's happened but since I don't have one off the top of my head I'll instead point out a related issue: https://en.wikipedia.org/wiki/Stagefright_(bug)

It's worth pointing out that many, many, many things use the libav* library family.

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brigade ◴[] No.45791047[source]
Yes, I know that multimedia/image vulnerabilities are popular vectors for zero-click attacks. My point is that desktop players are not a vector for zero-click attacks, and ffmpeg has not generally been used in end-user situations that are targets of zero-click or drive-by attacks. Mostly because of the license, but still.

If the exploit chain involves the user downloading and opening a file, something like >99% of the time the next step already involves executable code (or Office macros), which makes any ffmpeg vuln completely useless.

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1. dpe82 ◴[] No.45792508[source]
Chrome uses ffmpeg's underlying libraries.

It's used way, way more than you think.

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2. brigade ◴[] No.45793149[source]
Yes, I’m quite familiar with that. Chrome is why I added the “generally” qualifier.

And to the best of my knowledge, there has not been any in-the-wild exploit against Chrome through the handful of ffmpeg codecs they enable. Not even pwn2own type competitions either, as I recall.

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3. dpe82 ◴[] No.45794298[source]
I guess I'm confused - are you trying to imply the lack of a thorough, publicly reported successful exploit (or us just not casually giving you one that you care about) means that we're all released from the responsibility of taking potential exploits seriously?