(A) There are three groups of emplyees:
1. The employees who just do their jobs and don't go onto the internet for personal reasons and only visit approved business related web sites. This group, though not a major threat, often uses Google or another search engine to "find" the site they are looking for. This group can inadvertantly click on a search engine link taking them to a malicious site designed and optimized specifically to cause a distracted user to allow malware downloaders to install new versions of infected content on the computer.
2. The employees who disregard your work network security concerns and install software such as LIMEWIRE and other Peer to Peer file sharing applications (These are file sharing uploading and downloading applications), they also install cute icons, cute mouse pointers, and all sorts of "innocent" junk from random sites not verified safe by any experts. Included in this random site download groups unintentional installations are pieces of software that allow the computer to run multiple instances of spam-email servers zombying the computer to the task of sending out tens of thousands of spam messages to lists of email addresses all day long. Also in this group of software are downloaders that continually add new infections not yet identifiable to antivirus to the computer. These applications are (amongst other things) designed to disable the computer's antivirus and firewalls. Once disabled the malware hacker bundle then initiates a call from the infected computer to hackers who then loop-back into the computer. Because they use a loop-back connection your PIX and SonicWall firewalls do not stop them since the "request" was made from inside your network. The loop-back connection allows hackers to see the screen of the user, to access any files on the computer or on the network, to transfer, change, corrupt or delete the files, and finally, to trash the computer or any of the other computers they have access to - all without anyone at work being wise. This is the most dangerous group of employees to your network.
3. The office hacker. This group often consists of just one employee wanting to play, but sometimes they are also mean spirited revengeful workers who plant "time bombs" also known as "logic bombs" created to delete files at a specific point in the future "just in case" they ever get fired. As long as they are working they continually update the date of execution to a point further in the future - until they are no longer there and can't update the instructions, at which point your network becomes a ticking time bomb with no-one to stop it. In major corporations there are industrial spies, such as the infamous ex-members of the KGB that were recruited in America by industry to spy on competitors. In most cases the kind of serious hackers you will hire are going to be looking to steal your business information, contacts, business model setup (your QuickBooks/Quicken databases etc.) and steal whatever else they can nose around in that they find interesting. This group will also use your network connection to the internet to hack into other systems on the internet, including other businesses as well as home users computers. This group does not tend to be very good at networking and often consists of "script kiddies" who are using tools programmed by the real programmer hackers. The problem with this (which is not obvious) is that unbeknownst to the office hacker he or she is often using tools that contain their own back-door loop-back software. This hidden sofware built within the office hackers software allows the real programmer and his cohorts to pick and choose all day amongst all sorts of various businesses to take anything they want from your network - financial data, business information and databases, contacts, passwords etc.
(B) Loop-back software is a godsend to network support professionals because it allows us to connect remotely to a network and administer multiple computers and keep your costs down to a minimum. One of the whole points of network administration is to be able to take good advantage of networking to perform our jobs. Controlled, authorized remote access has been around for decades throughout the world and is expanding at an ever increasing rate. This is where we have White Hats and Black Hats. The White Hats continually scan and monitor, the Black Hats continually work at morphing and eluding. Both must use stealth to be effective. Neither advertises to the other what tools they are using today, and each considers the other to be a threat.
(C) Having a PIX or SonicWall firewall as security is like living in a walled in community but having only an electronic gate for security without having a police force outside, without having a human gatekeeper checking vehicles that come in, or a security force working to patrol inside the walls. Even the most serious person can inadvertantly let someone unwanted in. Those who don't care about security will let anyone who has an interesting story in. And finally there are the unwanted residents who slipped in past screening who are willing to rob you and everyone else - and don't care who else they let in.
(D) Social engineering is one important tool hackers use to map out and diagram a logical footprint of company network topologies and running services. Social engineering can take on many guises. In some instances someone dressed in a service uniform will arrive at a business when the owner is not present claiming to be someone they are not with the purpose of gaining access to your network. In other cases they may call claiming to be a support technician working for one of your software vendors (they sometimes gain initial information from employees overheard at lunch, through a previous call, or by dumpster diving through your trash after hours). In any case they usually prey upon the good nature of the person whom they contact by pretending they are going to be in big trouble with their company bosses if they don't get the job done. Once conned, the employee usually goes out of his or her way to help, and often participates.
