By default, CST will catch any common signal produced by any test that could indicate a crash. This feature can be disabled by executing CST with the -nosig or -nosignal flag.
You can learn exactly how crash detection works on a technical level here.
Signals detected by CST are currently the following:
SIGABRT
SIGFPE
SIGILL
SIGSEGV
SIGBUS
SIGINT
SIGTERM
SIGQUIT
SIGHUP
You can use the CST_BEFORE_ALLlifecycle hook to use your own signal handler if you want.