The DMO_VideoDecoder_Open function in loader/dmo/DMO_VideoDecoder.c in MPlayer 1.0rc1 and earlier, as used in xine-lib, does not set the biSize before use in a memcpy, which allows user-assisted remote attackers to cause a buffer overflow and possibly execute arbitrary code, a different vulnerability than CVE-2007-1387.
The product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary. This may result in read or write operations on unexpected memory locations that could be linked to other variables, data structures, or internal program data.