🚀 go-pugleaf

sjr@afterlife.ncsc.mil (Stephen J. Roznowski) writes:

>I'm busy looking for potential security holes in a suid root program.

>Currently, the program does the following:

>	system("/bin/stty -echo ...");

>Now, I realize that the "exec-ed" program also has to be "trusted",
>or there is a security hole (i.e. If I can replace /bin/stty, all
>bets are off).

>Now suppose that I do "all the correct things" before issuing the
>"system" call (set IFS, etc.) is this worse/same as the following:

>	tcgetattr(fd, &t);
>	t.c_lflag &= ~ECHO;
>	tcsetattr(fd, TCSANOW, &t);

The best things is to totally kill the environment. You'll never
no what kind of environment variables will be used for whatever purpuse
in future. Currently IFS, all variables starting with LD_ (on Suns), TERM
and PATH are the potentially dangerous ones (that I know of).
-- 
						|	Casper H.S. Dik
						|	casper@fwi.uva.nl