LibTIFF is vulnerable to denial of service (DoS). There is a Null-Pointer Dereference in the tif_print.c TIFFPrintDirectory function, as demonstrated by a tiffinfo crash.
bugzilla.maptools.org/show_bug.cgi?id=2770
www.securityfocus.com/bid/102345
gitlab.com/libtiff/libtiff/commit/c6f41df7b581402dfba3c19a1e3df4454c551a01
lists.debian.org/debian-lts-announce/2018/01/msg00033.html
lists.debian.org/debian-lts-announce/2018/01/msg00034.html
usn.ubuntu.com/3602-1/
usn.ubuntu.com/3606-1/
www.debian.org/security/2018/dsa-4100