An exploitable heap-based buffer overflow exists in the handling of TIFF images in LibTIFF's TIFF2PDF tool. A crafted TIFF document can lead to a heap-based buffer overflow resulting in remote code execution. Vulnerability can be triggered via a saved TIFF file delivered by other means.
https://security.gentoo.org/glsa/201701-16
http://www.securityfocus.com/bid/93902