parser.c in libxml2 before 2.9.5 does not prevent infinite recursion in parameter entities.
https://usn.ubuntu.com/3739-1/
https://lists.debian.org/debian-lts-announce/2022/04/msg00004.html
https://lists.debian.org/debian-lts-announce/2017/11/msg00041.html
https://github.com/GNOME/libxml2/commit/899a5d9f0ed13b8e32449a08a361e0de127dd961
https://bugzilla.gnome.org/show_bug.cgi?id=759579
https://blog.clamav.net/2018/07/clamav-01001-has-been-released.html