What’s a Trojan Horse virus?
Trojan Horse virus
What’s a Trojan Horse virus?
A Trojan Horse is an email virus usually released by an email attachment. If opened, it will scour your hard drive for any personal and financial information such as your social security, account, and PIN numbers. Once it has collected your info, it is sent to a thief’s database.
Now, there are Trojan Horses and there are viruses, but there's no such thing as a Trojan Horse virus. In fact, the very definition of each precludes any chance of there being such a thing. A Trojan does not replicate. Viruses do. That fact alone means there can never be a "Trojan Horse virus".
The Visa description continues with, "A Trojan Horse is an email virus usually released by an email attachment." Not so. A Trojan may be sent as an attachment in email, but it's certainly not an email virus. (In fact there are few true email viruses, but that's a whole other topic). So it may or may not arrive in email, and it's equally likely to have been downloaded from a website or resulted from a P2P file transfer. In other words, vector has nothing to do with whether something is or isn't a Trojan.
Just what is a Trojan then? A Trojan is a program that appears to be legitimate, but in fact does something malicious. Quite often, that something malicious involves gaining remote, surreptitious access to a user's system. Unlike viruses, a Trojan does not replicate (i.e. infect other files), nor does it make copies of itself as worms do.
There are several different types of Trojans. Some of these include: remote access Trojans (RATs), backdoor Trojans (backdoors), IRC Trojans (IRCbots), and keylogging Trojans. Many Trojan encompass multiple types. For example, a Trojan may install both a keylogger and a backdoor. IRC Trojans are often combined with backdoors and RATs to create collections of infected computers known as botnets.
But one thing you probably won't find a Trojan doing is scouring your hard drive for personal details, as the Visa description alleges. Contextually, that would be a bit of a trick for a Trojan. Instead, this is where the keylogging functionality most often comes into play - capturing the user's keystrokes as they type and sending the logs to the attackers. Some of these keyloggers can be pretty sophisticated, targeting only certain websites (for example) and capturing any keystrokes involved with that particular session.
But why is it important to know the difference between a virus, a worm, and a Trojan? Because a virus infects legitimate files, thus if antivirus software detects a virus, that file should be cleaned. Conversely, if antivirus software detects a worm or a Trojan, there is no legitimate file involved and action should be to delete the file.
After a recent incident ,an unknown entity trying to download a bank command into my computer to get my bank accounts information, I suspended all Internet banking operations.
It does not make sense the financial institutions to secure their systems if the weak link in the security is me ,and I do not have or will have the means to secure my computer.Also I concluded that is logically and physically imposible to secure any computer system.
I read your explanation of Trojan several times. But I still don’t know what to do with a trojan. Your instructions say “delete the file”. How will I know which file to delete? How will I recognize the trojan? If my antivirus doesn’t quantine the trojan, how do I protect my computer from it.
Your article is full of information, but I haven’t a clue what to do with the information. Could you write something in plain English, please?
submitted respectfully,
“…if antivirus software detects a virus, that file should be cleaned… if antivirus software detects a worm or a Trojan (the) action should be to delete the file.”
When the antivirus software detects the threat, it may prompt your for an action. Choose ‘clean’ for viruses, and ‘delete’ for worms and Trojans.
I contracted the BackDoor-AWV virus, even though I have McAfee Suite installed and current. I cannot Delete, Quarantine or Remove. McAfee warns me that the virus is present, but cannot help with the removal, nor does it recognize the name when I enter the name on their customer support site. Any suggestions?
Not the most lucid explanation I’ve ever read.
If folks didn’t have a pretty good idea what viruses, Trojan horses, and worms were before they read this explanation, they sure didn’t pick up much from this piece.
I think you know what you’re talking about, but you could have expressed yourself a lot more clearly.
I am sorry you are having difficulty understanding the material. Perhaps if you can explain just what part of it you did not understand, I can better respond to your comments. You may find “What is a Virus of help.
Hi Sharon,
If you can, please post your question to the antivirus forum. That way, other members will benefit as well. Plus, it may take a bit of back and forth to resolve your issue, and that’s outside of the scope of this comments section.
So a infector is a worm or virus?
I found the info fairly informative although I need to know a lot more in this area. As the lady said, if your computer says I have a Trogen, how do I know which file(s) it is in so that I can only delete those affected files. I am also interested in knowing more about GAIN.exe and other support cookies regarding which one’s do I have to use and need and which one’s will be a problem for me. I have accessed some websites on them, but found myself bogged down in unfamiliar information. I plan on signing up for your website for a while. This might help.
The article was well written and totally understandable. Thank you!
Thanks for the article. I got a trojan horse and was able to delete the file using Avast! antivirus software, but now I cannot get onto the internet.. I’ve tried unplugging the modem and plugging it back in as a friend advised, but it didn’t help.. any suggestions?
I found this article to be very informative. I THINK I got rid of the Trojan last night using AVG, but I’m afraid that it will return. Is that possible? Is it ok to have more than one anti-virus agent for extra protection?
of course it can always be a good thing to have more than 1 program for virus protection, i reccommend the following ones:
spybot – search & destroy (free download)
ad-aware SE personal (free download)
webroot’s spysweeper (costs $40 for 2 years, it really is the best thing out there in my opinion. worth the money)
the main place you’re gonna get those viruses (of course you’ve heard it a million times) porn, and downloads from ’suspicious’ sites. limewire of course, but that’s really only if you’re not careful about how you use it. bottom line, stop downloading so many odd/illegal programs/videos/pics/porn/songs
(i’m a hypcrite myself on that part, lol. but i know what i’m doing.)
*hypocrite
I have my antivirus software find two trojan viruses today and two a couple weeks ago and it says it quarantined them. They were in my temporary internet files. I deleted these files after finding out that’s where my antivirus software found them but, should I do anything else?
i have this trojan horse downloader agent that infects my system, i have it scanned and removed everytime the AVG detects threats from it but now that i have idea that this virus came from a website for downloading games, does this mean i cant download anything on that site anymore? can i just healed the virus and install the game to my computer anyway? thanks..
I’m currently writing a case study on this topic and trying to understand it, therefore starting from scratch. can these trojans be found on social networking sites? If so, do you happen to know any specific ocurences in the past where this has been proven an issue?
My computer just detected a trojan and said that disinfect was recommended; when I click okay it said that it could only rename it .. but I have just scanned my computer and its not picking anything up. does this mean its still there? and can the trojan tamper with my anti virus software so that it doesn’t show up?
there is such thing as trojan horse i almost got infected with it on myspace good thing i have avast and it stoped it from anything from downloading : )
but if you want to check it out go to FIND FRIENDS then look for this name Proxy – “spotproxy.com”. TROJAN HORSE IS REAL BE ON THE LOOK OUT OK
this has nothing to do with this but if anyone can help me with the name of this virus
discription: thing comes out of egg; starts growling; makes a hole in the backround;and destroys my computer.
please help
what is an example of the trojan virus??
well well well its not a virus aye well thats what it’s called so ummm i presume it it 1
It says I have a Trojan virus on my iPod but idk how I could recieve an email virus on it when I have not used it for email.
As the topic of the article discusses, a trojan isn’t a virus. So one cannot have a trojan virus. I’m not sure what the email question is regarding. Malware spreads via many vectors. An iPod is pretty much just a portable hard drive with specialized software. If you can transfer files onto something, you can transfer malware as well.
A Trojan virus attached to my flash drive after I used it on an infected computer. If a Trojan does not infect other areas, how is this possible? The exact name was “Trojan horse Dropper.Generic.ZMN” I have scanned my computer several times and it’s not on my computer. So why would it transfer to a flash drive and not a computer?
my mom says that Trojan infestation, but can you honestly know what to look for when trying to find the source of the infestation?
this is all very confusing.
today someone got into my hotmail account and e mailed all of my contacts using my name as the sender… the only reason i knew this is because I have another screen name and it is on my contact list as well. so I was shocked to see mail from myself. how did they do this??? and what is this called and how do I prevent this from happening again.
I have AVG and when i scanned my pc it did not show anything odd except cookies. So what do I do now????
Okay, I did a scan and I have 32 viruses. I have disconnected the iternet already, but not sure what to do know. Is there anyay to get rid of it wihout getting an antivirus? I need some help and fast.
Hi
B-)
Last week the computer flashed up on the Screen TROJAN in very large letters.This was accompanyed by a verl lound Klaxon sound from the computer.Does this mean that the Trojan has breached the computers defense system.?
All seems to be operating as Normal
theres a serious problem with my computer. ok so i start it up and the dell screen comes up. then it says that windows did not start successfully and that i should select last known good configuration. so i pick that and a blue screen comes up and it says that there is a problem on my computer and it needs to be shut down to protect my computer. i have no idea whats wrong with it but i cant get past the blue screen. if anyone has even the slighest idea how to fix this problem i would really appreciate it. thanks:)
i have a trojan virus on my computer,it will not let me delete it & when i tried to use your free virus removal tool,it blocks me,i just want this to be deleted from my computer
Trojan needs to Die. D:
Tonight my computer was infected with “Trojan.Win32.Agent.azsy” what is that? It says it copies its body to the current user’s window startup directory and attempts to steal passwords. We have 385 threats. What should I do? Could I have gotten this from a website, because it all came up right after I had clicked on a Site about Farrah Faucets death. Our Pc has been running a little slow, so we had already thought that something was going on. So Please tell me what you think! I am scared and in need of desperate help. Thanks
it also diguised as a game or something like that
my antivirus is kaspersky that is a nice antivirus