csstart program in iCal 2.1 Patch 2 uses relative pathnames to install the libsocket and libnsl libraries, which could allow the icsuser account to gain root privileges by creating a Trojan Horse library in the current or parent directory.
iCal 2.1 Patch 2 installs many files with world-writeable permissions, which allows local users to modify the iCal configuration and execute arbitrary commands by replacing the iplncal.sh program with a Trojan horse.