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What file types can contain or be viruses?

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youngbuck

Member
Joined
Aug 30, 2002
Location
CO, USA
Obviously an executable file can be a virus... but what other types of files can be viruses or contain viruses? I mean, obviously a plain ol' text files with the .txt extension isn't going to have a virus. I mainly want to know so I know how to configure my virus scanner properly. No need having it scan thousands of files that can't be viruses.

Thanx in advance,
-YB
 
I hate to burst your bubble but viruses can be hidden in a *.txt file. I don't think there are any file types that are immune to infection of some sort. Any virus code in a *.txt file is inert in that file as long as the .txt isn't changed to another file type.
 
I agree. When running a virus scan its best to just scan all files. I have been sent .doc files that have been virus infected before. Just run a full system scan and go get a cup of coffee and read a book for a while :)

SavageBasher said:
Anything can be a virus. Take an exe and rename it to a jpg. Now it looks like a jpg, but its still a virus.
 
Any file can be a virus... And keep in mind that you don't have to directly execute the file (AKA you don't have to be a complete idiot to run the virus). Example:

I just got a case today where a user had 13 virus infections in files that are associated with autoCAD drawings... When the user opens the drawings, the virus has replaced associated files and is automatically executed by the program opening the drawing.
 
jpegs can be a virus. we just had a problem on another forum i'm part of where someone hotlinked their avatar from some website and the jpeg contained a virus and infected numerous members when they loaded a thread the guy with the avatar posted on. this was not a renamed exe it had the picture show up.

if you want to configure your AV properly have it scan everything and don't look for things to exclude
 
Since most image formats have comment fields, even valid images can contain a virus, although it would be difficult to execute them by accident. This page demonstrages that code can be hidden in jpgs and pngs and has some links to related sites.
I'm not saying that you should never look at jpgs for fear of getting a virus, but you shouldn't leave anything out when scanning for viruses either.

edit: For clarity, I realize that the site I linked to has compressed code embedded in images, and that you have to compile the code before it will do anything. You could use a similar technique to stick an executable in an image.
 
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twump said:
jpegs can be a virus. we just had a problem on another forum i'm part of where someone hotlinked their avatar from some website and the jpeg contained a virus and infected numerous members when they loaded a thread the guy with the avatar posted on. this was not a renamed exe it had the picture show up.

Twump, do you have any more information about this, i.e., the name of the virus, a URL with the thread in question, etc... I'd really like to have some concrete information from one of the "majors" like symantec to put before our IT department on this issue.
 
just do ctrl+alt+delete to see if any processes have been added or deleted
go to start-run-msconfig-startup and see if anything that you dont know of has been added
go to netstat -n in dos to see if any wierd connections have been added

AND THE SURE FIRE WAY TO KNOW. if your firewall is on and loads next time you start up and nothing asks to connect then your safe.
 
Scary, you must look in the unlikely places. Virus's are everywhere, just need to use some common sence and a good scanner.
 
Zatrix said:
just do ctrl+alt+delete to see if any processes have been added or deleted
go to start-run-msconfig-startup and see if anything that you dont know of has been added
go to netstat -n in dos to see if any wierd connections have been added

AND THE SURE FIRE WAY TO KNOW. if your firewall is on and loads next time you start up and nothing asks to connect then your safe.

Um, there are a lot of virii that will not be found by following those steps... I actually haven't come across any that can be found that way.
 
Zatrix said:
well as long as you download from trusted places you will be FINE

also as long as your firewall works its 99% impossible for a trojan to get you.

You will be FINE as long as the "trusted place" doesn't get hacked. ;)

The only firewall I use anymore is my Linksys router, I used to run Zonealarm also, but I had it for over a month and it caught nothing. :santa:
 
Someone told me its impossible to put a virus in an MP3, so as far as I know thats true. I'm not entirely sure if this is true, so enlighten me if I'm wrong and please back it up if you do. :)
 
That would be a good one, an mp3 with a virus. Could bring anti piricy memebers to a new level. EXTREME ANTI PIRICY MEMBERS beware, lol crazy idiots.
 
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