freebsd-ports/security/libparanoia/pkg-descr

This is a library, which contains a safe reincarnations
of strcpy/strcat/sprintf and some other functions,
which is known to be a source to 99% of stack smashing 
attacks since Morrison Worm. 

Basic idea is: these functions never return in case 
of modified stack frames. Instead, they kills current
process with SIG_SEGV, and, in case when program 
just ignores it - calls exit(2). In 'paranoidal'
point of view, termination of a process is a much 
less worth, than possible incorrect continuation.

This library can be used in two ways - you can just 
install it as a port/package, and then relink critical
applications (such as a network daemons) with 
-lparanoia -L/usr/local/lib, or you can override
standard functions in libc (using libparanoia/copy-to-libc 
shell script) - in this case you'll get any application,
which uses shared libc, automatically protected.

WWW: http://www.lexa.ru/snar/libparanoia/
-- 
Alexandre Snarskii <snar@paranoia.ru>. 	Baltika-3 is better :)