mpv -- arbitrary code execution via crafted website

mpv developers report:

mpv through 0.28.0 allows remote attackers to execute arbitrary code
via a crafted web site, because it reads HTML documents containing
VIDEO elements, and accepts arbitrary URLs in a src attribute without
a protocol whitelist in player/lua/ytdl_hook.lua. For example, an
av://lavfi:ladspa=file= URL signifies that the product should call
dlopen on a shared object file located at an arbitrary local pathname.
The issue exists because the product does not consider that youtube-dl
can provide a potentially unsafe URL.