An issue was discovered in GNU LibreDWG 0.7 and 0.7.1645. There is a NULL pointer dereference in the function dwg_dxf_LTYPE at dwg.spec (earlier than CVE-2019-9776).
https://savannah.gnu.org/bugs/index.php?55893
https://github.com/LibreDWG/libredwg/issues/99
http://www.securityfocus.com/bid/107447
http://lists.opensuse.org/opensuse-security-announce/2020-01/msg00045.html
http://lists.opensuse.org/opensuse-security-announce/2020-01/msg00033.html