The dccp_rcv_state_process function in net/dccp/input.c in the Linux kernel through 4.9.11 mishandles DCCP_PKT_REQUEST packet data structures in the LISTEN state, which allows local users to cause a denial of service (invalid free) or possibly have unspecified other impact via an application that makes an IPV6_RECVPKTINFO setsockopt system call. http://www.cve.mitre.org/cgi-bin/cvename.cgi?name=2017-6074