fcgid_spawn_ctl.c in the mod_fcgid module 2.3.6 for the Apache HTTP Server does not recognize the FcgidMaxProcessesPerClass directive for a virtual host, which makes it easier for remote attackers to cause a denial of service (memory consumption) via a series of HTTP requests that triggers a process count higher than the intended limit.
bugs.debian.org/cgi-bin/bugreport.cgi?bug=615814
www.debian.org/security/2012/dsa-2436
www.openwall.com/lists/oss-security/2012/03/15/10
www.openwall.com/lists/oss-security/2012/03/16/2
www.securityfocus.com/bid/52565
exchange.xforce.ibmcloud.com/vulnerabilities/74181
issues.apache.org/bugzilla/show_bug.cgi?id=49902