An issue was discovered in CImg v.220. A double free in load_bmp in CImg.h occurs when loading a crafted bmp image.
https://usn.ubuntu.com/4039-1/
https://lists.debian.org/debian-lts-announce/2020/10/msg00033.html
https://lists.debian.org/debian-lts-announce/2019/09/msg00030.html