Speedfan.sys in Alfredo Milani Comparetti SpeedFan 4.33, when used on Microsoft Windows Vista x64, does not properly check a buffer during an IOCTL 0x9c402420 call, which allows local users to cause a denial of service (machine crash) and possibly gain privileges via unspecified vectors.
Improper Restriction of Operations within the Bounds of a Memory Buffer The product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary.