Multiple buffer overflows in vorbis_dec.c in the Vorbis decoder in FFmpeg, as used in Google Chrome before 8.0.552.237 and Chrome OS before 8.0.552.344, allow remote attackers to cause a denial of service (memory corruption and application crash) or possibly have unspecified other impact via a crafted WebM file, related to buffers for (1) the channel floor and (2) the channel residue.