The pidfile_write function in core/pidfile.c in keepalived 1.2.2 and earlier uses 0666 permissions for the (1) keepalived.pid, (2) checkers.pid, and (3) vrrp.pid files in /var/run/, which allows local users to kill arbitrary processes by writing a PID to one of these files.
bugs.debian.org/cgi-bin/bugreport.cgi?bug=626281
lists.debian.org/debian-security/2011/05/msg00012.html
lists.debian.org/debian-security/2011/05/msg00013.html
lists.debian.org/debian-security/2011/05/msg00018.html
openwall.com/lists/oss-security/2011/05/10/5
openwall.com/lists/oss-security/2011/05/16/7
secunia.com/advisories/44460
www.osvdb.org/72380
www.securityfocus.com/bid/47859
bugzilla.redhat.com/show_bug.cgi?id=704039
exchange.xforce.ibmcloud.com/vulnerabilities/67477