Hacked: Who Else Is Using Your Computer?

A friend called me one day and asked if I would stop by to look at his computer. He said it was running abnormally slow and he had found something on his hard-drive he could not explain. I could almost guess what it was he found. Have I been hacked?

You see, his computer had been hacked. Actually, in his case, his computer had been tagged. Similar to the image you see here.

Tag, You're It!
---------------
The file transfer protocol, commonly referred to as "FTP", has been around for many years. In the early days of the Internet, it was one of the few ways to easily upload and download files from one computer to another. Many commercial operating systems come with an FTP server installed. In other cases, the option for FTP services is selected by a user when they are installing or updating their operating system. If this service is not setup properly, or you don't have an adequately configured software or hardware firewall, it is an open invitation for a hacker or intruder.

FTP Tagging - The most common purpose for someone to compromise your FTP server is for the storage and distribution of illegally obtained software and files. This could include cracked software, stolen movies, audio files, and pornography. Removing this type of contraband from your computer can be difficult, particularly if you are using a Microsoft Windows platform. Hackers use sophisticated scripts to create a maze of directory structures to house their wares on your computer. They may use a combination of names with spaces in them, and in some cases use extended characters (characters outside the normal alpha-numeric range). Deleting these directories through normal means may be difficult, if not impossible, for the average user. Many people wind up wiping their system and re-installing it, and that is if they're lucky enough to find out their system has been compromised.

The above is a perfect example of why the statement, "I'm not worried about being hacked. What do I have that a hacker would want?" is not a good position to take. The fact is, you do have something they want, your computers resources. Why should a hacker store tons of illegally obtained files on their systems when they can use yours.

The Good, The Bad, And The Ugly
-------------------------------

The Good
--------
When I was young I use to spend hours upon hours on the Internet Relay Chat, also know as the IRC. The IRC is another method of Internet communication, which has been around for quite a long time. When I was a frequent user of the IRC, it was just plain fun. You would meet all kinds of people from all over the world. It was the instant messenger of the time.

The Bad
-------
Today, the IRC is a huge communications network. It is made up of thousands of channels, and can be accessed by pretty much any operating system platform. It is also a favorite means of communication for hackers. They can discuss new exploits, methods of compromise, and even send and receive files. Many hacker groups use a cryptic language to communicate with each other on the IRC channels. Unless you know the language constructs they use, their conversations can look like a bunch of nonsense.

There are many exploits, backdoors, and Trojans that effect, or are contained in, the myriad of IRC clients on the Internet. Making sure you choose one that's relatively safe to use is not an easy task. As an example, take a look at this list of IRC safety and security info at irc.org.

The Ugly
--------
It's not just the exploits and security risks associated with using the IRC, which need to concern you. If a hacker is able to install an IRC relay agent on your computer, it can become a conduit through which they communicate and distribut