On Mon, 2 Feb 2004, Geoffrey wrote:
John wrote:
Thanks Ralf.
Definitely, mac spoofing is quite hard, isn't?
Depending on the hardware, it's not difficult at all. See the -H option at:
Mac spoofing is quite easy to do. It can easily be accomplished even by amateurs. Most low end firewalls and routers offer it as a feature to circumvent PPOE restrictions on single MAC addresses.
Can iptables be cracked? What vulnerabilites exist regarding iptables?
I am not aware of any documented case of IP Tables failing. It's easy to misconfigure your firewall script, however. IPTables operates at the kernel level, and it's conceiveable that some clever shithead could write a kernel module that alters IPTables' behavior in a way that nullifies it's protection of your server. Remember, a rootkit gives anyone who accesses it absolute power over the server to do anything they want, including poisoning your detection mechanisms. There is no such thing as perfect security. The best you can hope for is "adequate", and adequate is defined on a constantly changing sliding scale. Additionally, most of the time confirmation that your security policy is inadequate or insufficient comes after a breakin. Apply the tightest policy your users and management will allow, and constantly push for tighter control of the network. You will not regret it. -- -linux_lad ICQ 115601915 pub key on request