What is Trojans?

Definition: A Trojan is a self-contained program that appears to be legitimate, but in fact does something malicious. Trojans do not infect other files as viruses do, nor do Trojans make copies of themselves as worms do.

Many of the the earlier Trojans were used to launch Distributed Denial of Service (DDoS) attacks, such as those suffered by Yahoo and eBay in the latter part of 1999. Today, Trojans are most often used to gain backdoor access - that is to say remote, surreptitious access - to a user's system.

There are several different types of Trojans: Remote Access Trojans (RAT)

, Backdoor Trojans (backdoors), IRC Trojans (IRCbots), and Keyloggers. Many of these different types can be employed in a single Trojan. For example, a keylogger that also operates as a backdoor may commonly be disguised as a game hack. IRC Trojans are often combined with backdoors and RATs to create collections of infected computers known as botnets.

How did I get infected?

Trojans are executable programs, which means that when you open the file, it will perform some action(s). In Windows, executable programs have file extensions like "exe", "vbs", "com", "bat", etc. Some actual trojan filenames include: "dmsetup.exe" and "LOVE-LETTER-FOR-YOU.TXT.vbs" (when there are multiple extensions, only the last one counts, be sure to unhide your extensions so that you see it). More information on risky file extensions may be found at this Microsoft document.

Trojans can be spread in the guise of literally ANYTHING people find desirable, such as a free game, movie, song, etc. Victims typically downloaded the trojan from a WWW or FTP archive, got it via peer-to-peer file exchange using IRC/instant messaging/Kazaa etc., or just carelessly opened some email attachment. Trojans usually do their damage silently. The first sign of trouble is often when others tell you that you are attacking them or trying to infect them!

How do I avoid getting infected in the future?

You must be certain of BOTH the source AND content of each file you download! In other words, you need to be sure that you trust not only the person or file server that gave you the file, but also the contents of the file itself.

Here are some practical tips to avoid getting infected (again).

1. NEVER download blindly from people or sites which you aren't 100% sure about. In other words, as the old saying goes, don't accept candy from strangers. If you do a lot of file downloading, it's often just a matter of time before you fall victim to a trojan.
2. Even if the file comes from a friend, you still must be sure what the file is before opening it, because many trojans will automatically try to spread themselves to friends in an email address book or on an IRC channel. There is seldom reason for a friend to send you a file that you didn't ask for. When in doubt, ask them first, and scan the attachment with a fully updated anti-virus program.
3. Beware of hidden file extensions! Windows by default hides the last extension of a file, so that innocuous-looking "susie.jpg" might really be "susie.jpg.exe" - an executable trojan! To reduce the chances of being tricked, unhide those pesky extensions.
4. NEVER use features in your programs that automatically get or preview files. Those features may seem convenient, but they let anybody send you anything which is extremely reckless. For example, never turn on "auto DCC get" in mIRC, instead ALWAYS screen every single file you get manually. Likewise, disable the preview mode in Outlook and other email programs.
5. Never blindly type commands that others tell you to type, or go to web addresses mentioned by strangers, or run pre-fabricated programs or scripts (not even popular ones). If you do so, you are potentially trusting a stranger with control over your computer, which can lead to trojan infection or other serious harm.
6. Don't be lulled into a false sense of security just because you run anti-virus programs. Those do not protect perfectly against many viruses and trojans, even when fully up to date. Anti-virus programs should not be your front line of security, but instead they serve as a backup in case something sneaks onto your computer.
7. Finally, don't download an executable program just to "check it out" - if it's a trojan, the first time you run it, you're already infected!

How do I get rid of trojans?!?

Here are your many options, none of them are perfect. I strongly suggest you read through all of them before rushing out and trying to run some program blindly. Remember - that's how you got in this trouble in the first place. Good luck!

1. Clean Re-installation: Although arduous, this will always be the only sure way to eradicate a trojan or virus. Back up your entire hard disk, reformat the disk, re-install the operating system and all your applications from original CDs, and finally, if you're certain they are not infected, restore your user files from the backup. If you are not up to the task, you can pay for a professional repair service to do it.

2. Anti-Virus Software: Some of these can handle most of the well known trojans, but none are perfect, no matter what their advertising claims. You absolutely MUST make sure you have the very latest update files for your programs, or else they will miss the latest trojans. Compared to traditional viruses, today's trojans evolve much quicker and come in many seemingly innocuous forms, so anti-virus software is always going to be playing catch up. Also, if they fail to find every trojan, anti-virus software can give you a false sense of security, such that you go about your business not realizing that you are still dangerously compromised. There are many products to choose from, but the following are generally effective: AVP, PC-cillin, and McAfee VirusScan etc.. All are available for immediate downloading typically with a 30 day free trial. For a more complete review of all major anti-virus programs. When you are done, make sure you've updated Windows with all security patches [ext. link].

3. Anti-Trojan Programs: These programs are the most effective against trojan horse attacks, because they specialize in trojans instead of general viruses. A popular choice is The Cleaner, $30 commercial software with a 30 day free trial. To use it effectively, you must follow hackfix.org's configuration suggestions [ext. link]. When you are done, make sure you've updated Windows with all security patches [ext. link], then change all your passwords because they may have been seen by every "hacker" in the world.

4. IRC Help Channels: If you're the type that needs some hand-holding, you can find trojan/virus removal help on IRC itself, such as EFnet #dmsetup or DALnet #NoHack. These experts will try to figure out which trojan(s) you have and offer you advice on how to fix it. The previous directions were in fact adapted from advice given by EFnet #dmsetup.

Why we need wireless network security?

Wireless security has never been taken seriously because we have always been using wired networks till this date. Many of you will say that such a lame reason! But, believe me that is a correct reason and I’ll explain it to you right now.

Wireless networks can be easily exploited by hackers as compared to any wired network and the reason is simple, our wireless network can be accessed by anyone who has a device with wireless capabilities and then can abuse the information stored on the network, but when it’s a wired network, then the person has to come down physically and connect to that network. Although, hackers know the tricks of penetrating in those networks too but at least you won’t be targeted that easily.

Why do you think that Wireless security is so important, I don’t have anything on my computer, which will benefit any other person ?

Good Question! Here are the reasons, for which you’ll agree to me that wireless security is important :

1. Do you use online banking services ? If the answer was yes, then believe me you leave lots of traces which can reveal lots of account related information. And same goes for Online shopping too. So, you can fear of losing bank account related information, credit card information. Would you like to compromise on information like that?

2. Your internet connection can be misused : Your internet connection can be misused by many people, and they may increase the cost of bandwidth and you may end up paying huge bills. There can be a case, where nasty people may try to send your internet connection to send spam and then you’ll be held liable for that. Would you like to see that happen to you ?

I’m sure the answer in both the cases must have been NO and so that means you agree to me that Wireless security is important!

What do I need to do to secure my home wireless network ?

There are few things which you can do to ensure that you’ll not give easy access to those who are eyeing on free internet connection or some important information stored on your computer :

1. Change the SSID : SSID is the case sensitive name assigned to a wireless network and it has to be used by each and every device in that network. By default, it is the manufacturer’s name but it is advisable to change that and make sure you don’t change it to anything identifiable for e.g. your name, address or anything like that.

2. Use WPA or WPA 2 : When it comes to security in wireless then prefer to use WPA or WPA 2 over WEP. WEP is very easy to break as compared to WPA or WPA 2, be it Static WEP or Dynamic WEP.

3. Use a strong and long key : With WPA, you have to specify a Pre-Shared Key (PSK) and which acts as a password to your network. Ensure that it has to be long (at least 20 characters long) and must not be any dictionary word. Dictionary attacks can be used to break the key.