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.
The product copies an input buffer to an output buffer without verifying that the size of the input buffer is less than the size of the output buffer, leading to a buffer overflow.