An issue was discovered in Exempi before 2.4.3. It allows remote attackers to cause a denial of service (invalid memcpy with resultant use-after-free) or possibly have unspecified other impact via a .pdf file containing JPEG data, related to XMPFiles/source/FormatSupport/ReconcileTIFF.cpp, XMPFiles/source/FormatSupport/TIFF_MemoryReader.cpp, and XMPFiles/source/FormatSupport/TIFF_Support.hpp.
https://usn.ubuntu.com/3668-1/
https://lists.debian.org/debian-lts-announce/2018/03/msg00013.html
https://cgit.freedesktop.org/exempi/commit/?id=c26d5beb60a5a85f76259f50ed3e08c8169b0a0c