[FFmpeg-devel] [RFC][PATCH] configure: Disable unsafe demuxers by default

[Carl Eugen Hoyos]

2018-05-10 17:44 GMT+02:00, Derek Buitenhuis <derek.buitenhuis at gmail.com>:
> These demuxers have probes that mainly probe based on file extension,
> and map to codec IDs that render text as video. The result is that
> ffmpeg will, by default, happily render, for example, .txt files
> as images. This is not exactly a good security practice, an only
> makes it easier for potential attackers to gain the contents of
> system files.
>
> Disable building these by default.
>
> Signed-off-by: Derek Buitenhuis <derek.buitenhuis at gmail.com>
> ---
> I've been hard disabling these at $dayjob for a long time, after some
> "interesting" upload attempts, but it should probably be done for
> everyone.
>
> I'm not overly attached implementaion details like the option name
> or whether it's done at build time ot runtime, but I think the concept
> of "don't render arbitrary system text files" is an important one.

Disabling demuxers by default does not seem to be a good idea to me.

Carl Eugen