The agroot() function in cgraph\obj.c in libcgraph.a in Graphviz 2.39.20160612.1140 has a NULL pointer dereference, as demonstrated by graphml2gv.
{ "urgency": "unimportant" }
"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2019-11023.json"