In libavformat/nsvdec.c in FFmpeg 2.4 and 3.3.3, a DoS in nsv_parse_NSVf_header() due to lack of an EOF (End of File) check might cause huge CPU consumption. When a crafted NSV file, which claims a large "table_entries_used" field in the header but does not contain sufficient backing data, is provided, the loop over 'table_entries_used' would consume huge CPU resources, since there is no EOF check inside the loop.
https://lists.debian.org/debian-lts-announce/2019/01/msg00006.html
https://github.com/FFmpeg/FFmpeg/commit/c24bcb553650b91e9eff15ef6e54ca73de2453b7