The parse_string function in cjson.c in the cJSON library mishandles UTF8/16 strings, which allows remote attackers to cause a denial of service (crash) or execute arbitrary code via a non-hex character in a JSON string, which triggers a heap-based buffer overflow.
https://raw.githubusercontent.com/esnet/security/master/cve-2016-4303/esnet-secadv-2016-0001.txt.asc
https://lists.debian.org/debian-lts-announce/2020/01/msg00023.html
https://github.com/esnet/iperf/commit/91f2fa59e8ed80dfbf400add0164ee0e508e412a
http://software.es.net/iperf/news.html#security-issue-iperf-3-1-3-iperf-3-0-12-released
http://lists.opensuse.org/opensuse-updates/2016-08/msg00090.html
http://lists.opensuse.org/opensuse-updates/2016-08/msg00082.html