FFmpeg through 9.0.2 contains an out-of-bounds read vulnerability in the Cook decoder joint_decode() function because…

FFmpeg through 9.0.2 contains an out-of-bounds read vulnerability in the Cook decoder joint_decode() function because cook_decode_init() does not check js_subband_start against subbands. Attackers can supply a crafted RealMedia file whose extradata causes reads past decode_buffer_0, leaking pointers and decoder state into decoded audio to help defeat ASLR.