The sctpsfdo51Dce function in net/sctp/smstatefuns.c in the Linux kernel through 3.13.6 does not validate certain authenable and authcapable fields before making an sctpsfauthenticate call, which allows remote attackers to cause a denial of service (NULL pointer dereference and system crash) via an SCTP handshake with a modified INIT chunk and a crafted AUTH chunk before a COOKIE_ECHO chunk.