Integer signedness error in the NE2000 emulator in QEMU 0.8.2, as used in Xen and possibly other products, allows local users to trigger a heap-based buffer overflow via certain register values that bypass sanity checks, aka QEMU NE2000 "receive" integer signedness error. NOTE: this identifier was inadvertently used by some sources to cover multiple issues that were labeled "NE2000 network driver and the socket code," but separate identifiers have been created for the individual vulnerabilities since there are sometimes different fixes; see CVE-2007-5729 and CVE-2007-5730.

The NE2000 emulator in QEMU 0.8.2 allows local users to execute arbitrary code by writing Ethernet frames with a size larger than the MTU to the EN0_TCNT register, which triggers a heap-based buffer overflow in the slirp library, aka NE2000 "mtu" heap overflow. NOTE: some sources have used CVE-2007-1321 to refer to this issue as part of "NE2000 network driver and the socket code," but this is the correct identifier for the mtu overflow vulnerability.