Apache HTTP Server Vulnerability - CVE-2007-3304
Apache httpd 1.3.37 2.0.59 and 2.2.4 with the Prefork MPM module allows local users to cause a denial of service by modifying the worker_score and process_score arrays to reference an arbitrary process ID which is sent a SIGUSR1 signal from the master process aka quotSIGUSR1 killer.quot