An issue was discovered in Exempi before 2.4.4. The TradQT_Manager::ParseCachedBoxes function in XMPFiles/source/FormatSupport/QuickTime_Support.cpp allows remote attackers to cause a denial of service (infinite loop) via crafted XMP data in a .qt file.
https://usn.ubuntu.com/3668-1/
https://lists.debian.org/debian-lts-announce/2018/03/msg00013.html
https://cgit.freedesktop.org/exempi/commit/?id=886cd1d2314755adb1f4cdb99c16ff00830f0331