CVE-2017-5972 (http://nvd.nist.gov/nvd.cfm?cvename=CVE-2017-5972): The TCP stack in the Linux kernel 3.x does not properly implement a SYN cookie protection mechanism for the case of a fast network connection, which allows remote attackers to cause a denial of service (CPU consumption) by sending many TCP SYN packets, as demonstrated by an attack against the kernel-3.10.0 package in CentOS Linux 7. NOTE: third parties have been unable to discern any relationship between the GitHub Engineering finding and the Trigemini.c attack code.
gentoo-sources-3.x no longer in portage tree. Marking as OBSOLETE