Ubuntu: (Multiple Advisories) (CVE-2017-9935): LibTIFF vulnerabilities

In LibTIFF 4.0.8, there is a heap-based buffer overflow in the t2p_write_pdf function in tools/tiff2pdf.c. This heap overflow could lead to different damages. For example, a crafted TIFF document can lead to an out-of-bounds read in TIFFCleanup, an invalid free in TIFFClose or t2p_free, memory corruption in t2p_readwrite_pdf_image, or a double free in t2p_free. Given these possibilities, it probably could cause arbitrary code execution.