The _TIFFVGetField function in tif_dir.c in libtiff 4.0.6 allows attackers to cause a denial of service (invalid memory write and crash) or possibly have unspecified other impact via crafted field data in an extension tag in a TIFF image.
https://security.gentoo.org/glsa/201701-16
http://www.securityfocus.com/bid/79699
http://www.securityfocus.com/archive/1/537205/100/0/threaded
http://www.oracle.com/technetwork/topics/security/ovmbulletinjul2016-3090546.html
http://www.oracle.com/technetwork/topics/security/linuxbulletinjul2016-3090544.html
http://rhn.redhat.com/errata/RHSA-2016-1547.html
http://rhn.redhat.com/errata/RHSA-2016-1546.html
http://lists.opensuse.org/opensuse-updates/2016-01/msg00100.html
http://lists.opensuse.org/opensuse-updates/2016-01/msg00081.html
http://lists.opensuse.org/opensuse-updates/2016-01/msg00078.html