In subst.c in zsh through 5.4.2, there is a NULL pointer dereference when using ${(PA)...} on an empty array result.
{ "versions": [ { "introduced": "0" }, { "last_affected": "5.4.2" } ] }
[ { "events": [ { "introduced": "0" }, { "last_affected": "17.10" } ] } ]
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2018-7548.json"