In ytnef 1.9.2, the TNEFFillMapi function in lib/ytnef.c allows remote attackers to cause a denial of service (memory consumption) via a crafted file.
https://usn.ubuntu.com/3667-1/
https://euvd.enisa.europa.eu/vulnerability/EUVD-2017-18405
https://blogs.gentoo.org/ago/2017/05/24/ytnef-memory-allocation-failure-in-tneffillmapi-ytnef-c/