Infected with Trojan

[Joseph Witchard]

Today, my computer was infected with a Trojan.Sasfis virus. Norton Internet Security has quarantined it and says that the threat has been resolved, and that no further action is needed. Is that true, even though it's only quarantined?

[max2474]

When a virus is quarantined by Norton, it cant be called upon without your knowledge. This basically means that your computer is safe from this instance of it.

The reason it is not deleted immediately is that anti-virus programmes do sometimes get it wrong about infected files, and so, just in case this "infected file" is actually a very important file, it will not delete it.

Of course, feel free to delete it yourself.

Hope this made sense.

[tirna]

I used to use NIS but switched to Trend Micro Internet Security a few years ago (but that's another story).

Like in TM, NIS from memory gives you the option of what to do when a virus/trojan is detected.

In TM you can tell it to

1) clean the infected file

2) if it can't be cleaned then to quarantine it or delete it

3) or just delete it without even trying to clean it.

NIS should have the same or similar options.

While in quarantine the file should be out of harms way.

[ChrisBR]

Like the other guys said you're basically safe...

I'd suggest running a slow scan through your anti virus, just to double check everything is good :)

[Jarrod1937]

Can't remember if norton supports this option, but if it does try doing a boot time scan. Some trojans can suppress warnings by an anti-virus/malware app while windows is running.

[Joseph Witchard]

If they're supported, do you run them directly from the software? And what is a "slow scan"?

[Jarrod1937]

If they're supported, do you run them directly from the software? And what is a "slow scan"?
You mean a boot time scan? Yeah, you schedule it, then restart your computer, it will boot to a mini version of the scanner before windows starts and scan.
A slow scan probably scans every file within the filesystem. The "fast" scans are usually faster because they only scan the common directories where malware hides.

[Joseph Witchard]

In the Scan Now menu, Norton gives the options of Quick Scan and Full System Scan. I always use the latter. Is Full System Scan the same as a slow scan?

[Jarrod1937]

In the Scan Now menu, Norton gives the options of Quick Scan and Full System Scan. I always use the latter. Is Full System Scan the same as a slow scan?
Yes, "Full System Scan" == slow scan.

[MacPC]

I rarely use Windows precisely for that reason, all the Trojan, malwares...
But I found this mbam http://www.malwarebytes.org/mbam.php useful on Windows. You never know what else infected your Windows PC, this is a free software you can download to scan and clean up your computer.

[Jarrod1937]

I rarely use Windows precisely for that reason, all the Trojan, malwares...
But I found this mbam http://www.malwarebytes.org/mbam.php useful on Windows. You never know what else infected your Windows PC, this is a free software you can download to scan and clean up your computer.
No offense to the original poster, but i never get malware of any type. You just have to use sense, you wouldn't believe how many trojans are installed because someone got an email, downloaded the attachment, unzipped it, then proceeded to double click on the executable file...
But if we're doing recommendations i'd recommend avast. They have a free home version. If you don't want to uninstall norton, you can do a custom install of avast that will just install the scanner, then you can do a boot time scan. Though it is generally best t scan with multiple tools, so you might as well give malwarebytes a try too, one always misses something that the other catches.

p.s. and macpc, keep in mind the mac os, nor linux is impervious to malware either, thankfully there is just a lower occurrence of it because of their lower market share (desktop market).

[Joseph Witchard]

Can viruses and such be downloaded by just visiting a certain website? I never download anything, from websites or email, unless it's a legit source. I don't even usually open email unless I know who it's from. But, every now and then, my computer is somehow infected.

[Jarrod1937]

Malware can install itself, without your permission, if it makes use of an exploit. For example, a few recent firefox patches were to fix an exploit that allowed a website to execute remote code. Though these exploits can exist in any program or system service.
However, you should still rarely get malware this way if you're not using unpatched, outdated versions of your software, and because the specific exploits must allow remote code to be executed, not just local arbitrary code.

[tirna]

I don't even usually open email unless I know who it's from..

Yes, that is the safest thing to do, but

out of curiosity, I've opened emails that my anti-virus has picked up as having an attachment with a virus and not been infected.

But opening and/or running the attachment is a big no-no. especially if the anti-virus was unable to clean it.

[MacPC]

Can viruses and such be downloaded by just visiting a certain website? I never download anything, from websites or email, unless it's a legit source. I don't even usually open email unless I know who it's from. But, every now and then, my computer is somehow infected.

Most definitely!! Rule of the thumb is, never download anything from people you don't know. Even if it's from people you know, scan it first. When you run into websites that offer you a free virus scan or registry scan, NEVER, NEVER do it. Scan your computer with trustworthy anti-virus program such as AVG. Two programs I highly recommend for Windows users is mbam, it's a malware scan program.
You can get a free copy from their site: http://www.malwarebytes.org/mbam.php
and CCleaner, also free, http://www.piriform.com/ccleaner

Just remember, with all these steps, it doesn't mean 100% fool prove so you still need to be vigilant. You can have a thousand locks on your doors, if someone wants to break in, he will find a way!

I am so glad I use Mac :)

[Joseph Witchard]

What about if you turn off JavaScript? (Note that I'm not willing to do this, I'm just speaking hypothetically.) Norton never liked the pop up ads that appeared when I would go to a site that used such ads. No JavaScript, no pop up ads, right?

[MacPC]

Javascript is only one of many ways to create pop-ups. A pop-up can also be done from HTML, and on the server side scripts such as php.

Generally, my feeling is that so many web sites use Javascript and it really limits your web experience if you turn it off.

Most browsers provide an option to block pop-ups, although it does not work 100%, it helps to reduce it.

Of course there are malice javascript out there, but if you turn it off, it's like you stop buying food for your house just because there is a little mouse in your kitchen. :)

[Joseph Witchard]

Most definitely!! Rule of the thumb is, never download anything from people you don't know. Even if it's from people you know, scan it first. When you run into websites that offer you a free virus scan or registry scan, NEVER, NEVER do it. Scan your computer with trustworthy anti-virus program such as AVG. Two programs I highly recommend for Windows users is mbam, it's a malware scan program.
You can get a free copy from their site: http://www.malwarebytes.org/mbam.php
and CCleaner, also free, http://www.piriform.com/ccleaner

Just remember, with all these steps, it doesn't mean 100% fool prove so you still need to be vigilant. You can have a thousand locks on your doors, if someone wants to break in, he will find a way!

I am so glad I use Mac :)

What exactly is the point of scanning something that someone has sent you? If you've already downloaded it, won't the virus (and possibly others that came with it) just duplicate themselves into areas other than the original file you downloaded?

[Jarrod1937]

What exactly is the point of scanning something that someone has sent you? If you've already downloaded it, won't the virus (and possibly others that came with it) just duplicate themselves into areas other than the original file you downloaded?
It won't install itself until you attempt to execute it. Thus scanning before you execute will, at least partially, tell you if it is safe or not.

[Joseph Witchard]

It won't install itself until you attempt to execute it. Thus scanning before you execute will, at least partially, tell you if it is safe or not.

You mean the downloaded program in question?

[MacPC]

On the Windows platform, usually when you click on a download link it will download a file with .exe extension. That is the installer, that's when you need to scan it, make sure you do that before running it. Even that, doesn't offer 1005 protection.

Some links tho, will indeed install without your knowledge. So be vigilant! :)

[Joseph Witchard]

On the Windows platform, usually when you click on a download link it will download a file with .exe extension. That is the installer, that's when you need to scan it, make sure you do that before running it. Even that, doesn't offer 1005 protection.

Some links tho, will indeed install without your knowledge. So be vigilant! :)

What if, for instance, the software came in a .zip folder? Is the only thing that needs to be scanned the executable file, or is it best to scan the entire folder?

[JunkMale]

IN ADDITION...

If you get an email from someone that has an attachment and you are not expecting one (attachment) then I would say your better asking your friend if they sent you an email with an attachment.

They can then verify if they did and if they didn't, you can be the first to inform your friend that they possibly have a trojan, etc.

as for MacPC... Like Linux, NO operating system is 100% safe, you mac is just as likely to be hacked or infected as is the window box. It depends on your security, the software you have on your system and if the virus has been specifically written to attack a Mac. I know of 2 cases where Macs were infected with viruses. You will find plenty of vendors doing AV software for the Mac.

[MacPC]

IN ADDITION...

If you get an email from someone that has an attachment and you are not expecting one (attachment) then I would say your better asking your friend if they sent you an email with an attachment.

They can then verify if they did and if they didn't, you can be the first to inform your friend that they possibly have a trojan, etc.

as for MacPC... Like Linux, NO operating system is 100% safe, you mac is just as likely to be hacked or infected as is the window box. It depends on your security, the software you have on your system and if the virus has been specifically written to attack a Mac. I know of 2 cases where Macs were infected with viruses. You will find plenty of vendors doing AV software for the Mac.

No computer is immune from a determined hacker. Only Mac and Linux have smaller market share so they are less targeted. But yea, being vigilant is the best and the only defense.

[MacPC]

What if, for instance, the software came in a .zip folder? Is the only thing that needs to be scanned the executable file, or is it best to scan the entire folder?

I would scan the entire file when possible.

[kschill]

just a matter of time before macs get hit. even the ipad was infected for windows user recently.

[MacPC]

just a matter of time before macs get hit. even the ipad was infected for windows user recently.

Hmmm, what do you mean? iPad and Windowss user?

I am not trying to start a Mac vs Windows debate. Like I said, if there is a will, there is a way, it's only a matter of time before Mac and Linux being targeted as their market share grow. No matter how you look at it, every OS, every program has its venerability. The fact of computer age. May the cat and mouse goes on!! :)

[JPnyc]

exactly. People who write malicious processes want to effect the largest user base possible. It's why I maintain the safest program of any type is the one the fewest people use.