Buffer overflow in the e1000_receive function in the e1000 device driver (hw/e1000.c) in QEMU 1.3.0-rc2 and other versions, when the SBP and LPE flags are disabled, allows remote attackers to cause a denial of service (guest OS crash) and possibly execute arbitrary guest code via a large packet.
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.