The outputSWF_TEXT_RECORD function (util/outputscript.c) in libming through 0.4.8 is vulnerable to an integer overflow and resultant out-of-bounds read, which may allow attackers to cause a denial of service or unspecified other impact via a crafted SWF file.
https://security.gentoo.org/glsa/201904-24
https://lists.debian.org/debian-lts-announce/2018/03/msg00008.html