Steve Gibson, "security researcher", founder of Gibson Research Corporation (GRC)


Steve Gibson's 16th podcast had some fascinating information about security for home users. Oh, and it was completely wrong.

 Steve: The thing that I've suggested to people whose email addresses I
 had was - and actually they wrote back and loved the idea. So I guess
 maybe it's feasible. It's possible to run two networks.

 Leo: Oh.

 Steve: There's nothing to prevent you from having your - and this
 actually solves the problem of people coming over to your house, also.

 Leo: So have an insecure network and a secure network.

 Steve: Exactly. You might want to run MAC address filtering and hide your
 SSID so that your neighbors are not using - I mean, I would suggest
 having one that is WPA running at full security, and probably just leave
 the other one wide open. Don't even bother with WEP security on the other
 one if you really don't care. But do use MAC address filtering...

 Leo: Just to keep it out of prying eyes.

 Steve: keep your neighbors from using it by mistake. Then your
 TiVos can connect, your Nintendo DS can connect, your neighbors who bring their
 laptops over...

 Leo: Real quickly, what would the topology be? You would have, okay, I
 have my cable modem or DSL modem. It's connected first to the insecure
 access point, and that's bridging to the secure access point?

 Steve: There are levels of security that you could go through. But as
 long as you've got a switch on your router which is isolating the traffic from
 each other, you're going to be very secure.

 Leo: Ah. So you have a router connected to the cable modem and a Wi-Fi
 access point coming off that router...

 Steve: Yup.

 Leo: ...that is open.

 Steve: And it's not going to see any of your - and none of your encrypted
 traffic would ever be decryptable anyway because you're on WPA.

 Leo: Right. So a modern router is going to have a switch, and it's going
 to be - that'll be sufficient. An older router might not, but...

 Steve: Yup.

Anyone on the open WiFi network would be able to scan the entire network. Home routers and routing devices generally do not allow you to segment a network to prevent one port (or series of ports) from accessing others. Further, having a switch does not absolutely prevent sniffing traffic. The popular Dsniff tool lets you do this.

 Steve: The way Ethernet works is that, essentially, anyone can talk on the
 wire at anytime they want.
 technology, it's called CSMA, Collision Sense Multiple Access. That's the
 original brilliant Ethernet technology that Bob Metcalfe invented back in
 the old days.

Close Steve, CSMA stands for Carrier Sense Multiple Access.

 Leo: Right. You've said that SSL connections are not susceptible to
 man-in-the-middle attacks, but I've read that they are. I want to believe
 you, but why do others think that SSL is susceptible to MITM attacks? And
 when an SSL or VPN authorizes, what stops someone listening to the
 packages each way to figure out the keys? So first let's start with what
 is a man-in-the-middle attack?

 Steve: Okay. In fact...

Steve said SSL connections are not susceptible to man-in-the-middle (MiTM) attacks? This is absolutely false. Such attacks have always been possible, and have been made even easier in the last year (2009/2010).

main page ATTRITION feedback