On Sat, 16 Jul 2011, Keith Roberts wrote: > To: CentOS mailing list <centos at centos.org> > From: Keith Roberts <keith at karsites.net> > Subject: Re: [CentOS] firewall? > > On Sat, 16 Jul 2011, Ljubomir Ljubojevic wrote: > > *snip* > >> I wrote about "physical presence *outside* of your network", like if >> you >> are on a large WISP that uses bridged network (bad design) and your >> Wireless client is bridged, and you have single NIC firewall in place, >> entire WISP's network will be able to sniff your traffic and hack into >> unprotected workstations/desktops. And there are those scenarios, much >> more then you can think. > > Which is why one poster mentioned that you need to be familiar with > IPtables and Networking before trying to make your machine(s) network(s) > secure? > > I read some time ago something about tunneling different protocols > through firewalls? which sounded quite scary. This is what I was refering to: Data Driven Attacks Using HTTP Tunneling "... HTTP Tunneling Example HTTP tunneling can be used to access ports that are normally inaccessible from a network. Consider Figure 1 below. The attacker's host is shown on the left with the target systems on the right. The router at the edge has the following policies:" http://www.symantec.com/connect/articles/data-driven-attacks-using-http-tunneling Sounds a bit scary to me, as any website needs to have port 80 open to allow access to that website. Kind Regards, Keith Roberts ----------------------------------------------------------------- Websites: http://www.karsites.net http://www.php-debuggers.net http://www.raised-from-the-dead.org.uk All email addresses are challenge-response protected with TMDA [http://tmda.net] -----------------------------------------------------------------