Security Basics mailing list archives
RE: Caching a sniffer
From: "Andrew Shore" <andrew.shore () holistecs com>
Date: Thu, 25 Mar 2004 16:30:05 -0000
Agreed, however, any activity that tricks a switch port into "opening up" usually requires someone to flood massive amount of traffic into the switch, this should alert any network manager to some kind of wrong doing plus in a large organisation all switches should be logging error event to some form of management server. Andrew Shore Senior Security Specialist DDI. 01302 308 165 andrew.shore () holistecs com Company Number 04943010 VAT Number 828 8635 82 Holistic Technologies Ltd Unit 7 Shaw Wood Business Park Shaw Wood Way Doncaster South Yorkshire DN2 5TB T. 0870 240 1442 F. 0870 240 1443 www.holistecs.com -----Original Message----- From: David Gillett [mailto:gillettdavid () fhda edu] Sent: 25 March 2004 16:21 To: Andrew Shore Cc: security-basics () securityfocus com Subject: RE: Caching a sniffer
A switch is not a hub/router. In fact it is a micro segmented bridge. A switch operates at layer 2 of the OSI model ie MAC address layer.
Amen, brother.
Therefore if someone has plugged a scanner into a network point they will not be able to sniff any useful information from the network unless that person has admin access to the switch. You can check this by ensuring that none of the ports on the switches are in span mode
While you need admin access to set up a span port, Shawn and I have alluded to two different techniques which can allow non-admin users to sniff traffic on a switched network. It's true that neither of these is quite "normal behaviour" -- they involve using special tools to modify the behaviour of hosts or switches. But the tools exist and are readily available, and so the issue that confronts admins is how to detect and/or frustrate their use. David Gillett --------------------------------------------------------------------------- Ethical Hacking at the InfoSec Institute. Mention this ad and get $545 off any course! All of our class sizes are guaranteed to be 10 students or less to facilitate one-on-one interaction with one of our expert instructors. Attend a course taught by an expert instructor with years of in-the-field pen testing experience in our state of the art hacking lab. Master the skills of an Ethical Hacker to better assess the security of your organization. Visit us at: http://www.infosecinstitute.com/courses/ethical_hacking_training.html ----------------------------------------------------------------------------
Current thread:
- RE: Caching a sniffer, (continued)
- RE: Caching a sniffer Byron Copeland (Mar 26)
- Re: Caching a sniffer Aaron (Mar 29)
- RE: Caching a sniffer David Gillett (Mar 25)
- RE: Caching a sniffer Andrew Shore (Mar 25)
- RE: Caching a sniffer Shawn Jackson (Mar 25)
- RE: Caching a sniffer Shawn Jackson (Mar 25)
- RE: Caching a sniffer David Gillett (Mar 26)
- RE: Caching a sniffer Shawn Jackson (Mar 25)
- RE: Caching a sniffer David Gillett (Mar 25)
- RE: Caching a sniffer Shawn Jackson (Mar 25)
- RE: Caching a sniffer Andrew Shore (Mar 25)
- RE: Caching a sniffer Shawn Jackson (Mar 25)
- RE: Caching a sniffer David Gillett (Mar 26)
- RE: Caching a sniffer Shawn Jackson (Mar 26)
- RE: Caching a sniffer Shawn Jackson (Mar 26)
- RE: Caching a sniffer Nero, Nick (Mar 26)
- Re: Caching a sniffer aruna (Mar 29)
- Re: Caching a sniffer Mitchell Rowton (Mar 30)