FastCGI (aka fcgi and libfcgi) 2.4.0 allows remote attackers to cause a denial of service (segmentation fault and crash) via a large number of connections.
https://exchange.xforce.ibmcloud.com/vulnerabilities/100696
https://bugzilla.redhat.com/show_bug.cgi?id=1189958
https://bugs.launchpad.net/ubuntu/+source/libfcgi/+bug/933417
https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=681591
http://www.openwall.com/lists/oss-security/2015/02/07/4