The IPv6 routing header parser in tcpdump before 4.9.2 has a buffer over-read in print-rt6.c:rt6_print().
https://support.apple.com/HT208221
https://security.gentoo.org/glsa/201709-23
https://github.com/the-tcpdump-group/tcpdump/commit/c7c515ee03c285cc51376328de4ae9d549e501a5
https://github.com/the-tcpdump-group/tcpdump/commit/3c4d7c0ee30a30e5abff3d6d9586a3753101faf5
https://access.redhat.com/errata/RHEA-2018:0705
http://www.tcpdump.org/tcpdump-changes.txt