The Linux kernel before 3.12.4 updates certain length values before ensuring that associated data structures have been initialized, which allows local users to obtain sensitive information from kernel stack memory via a (1) recvfrom, (2) recvmmsg, or (3) recvmsg system call, related to net/ipv4/ping.c, net/ipv4/raw.c, net/ipv4/udp.c, net/ipv6/raw.c, and net/ipv6/udp.c.
The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly.