Virus infecting files in a drive

[Peppermint]

So I think my laptop is infected with a virus/malware or something. It slowed down exponentially one time, when no other applications were open. I may be wrong, and if anyone would tell me why it slowed down, that would be great.

Anyway, I have a hard drive and I want to back up everything into it using Time Machine on my Mac. If I have a virus, could it infect the other files I had put into the drive years prior? If so, how could I filter out the virus?

If anyone would like to add any other information that might be helpful, please do!

Also, I’m now aware this is a PC forum, but I’m mostly talking about if the virus will infect the files that I’ve put in the drive years prior.

 

[DelJo63]

Anyway, I have a hard drive and I want to back up everything into it using Time Machine on my Mac. If I have a virus, could it infect the other files I had put into the drive years prior? If so, how could I filter out the virus?

This is all about how a virus spreads / propagates itself - - they vary from one to another. The system that is infected has little to do with your question.

But let's be clear on what you want to do first.

1. you have a system (the SUBJECT) which may or may not be infected
2. you want to backup everything on the SUBJECT to a drive on your Mac (perhaps using Time Machine as the tool)

What OS is running on the SUBJECT and how will you gain access to the hard drive on the Mac?

@Broni

 

[Peppermint]

This is all about how a virus spreads / propagates itself - - they vary from one to another. The system that is infected has little to do with your question.

But let's be clear on what you want to do first.

1. you have a system (the SUBJECT) which may or may not be infected
2. you want to backup everything on the SUBJECT to a drive on your Mac (perhaps using Time Machine as the tool)

What OS is running on the SUBJECT and how will you gain access to the hard drive on the Mac?

I’m not quite sure what you mean by what the OS running on the subject is. (Because I’m not too aware of vocabulary for computers) But, I’ll just be plugging in the hard drive, and then using Time Machine to back everything up to a folder that I would make in the drive. Again, sorry if I’m incorrectly comprehending your question.

 

[DelJo63]

Does the SUBJECT system run Windows or Mac OS X?

 

[Peppermint]

Does the SUBJECT system run Windows or Mac OS X?

My operating system is Mac OS X

 

[Cycloid Torus]

Backup: TWO (2) copies of your files on SEPARATE media - only counts when you have confirmed you have readable files on some other type of storage - a second and third HDD or SSD or Flash Drive or Cloud storage..

Once you are backed up, run your current AntiVIrus. Then consider running another AntiVirus ( https://www.pcmag.com/roundup/355173/the-best-mac-antivirus-protection ).

What do you find?

 

[Peppermint]

Backup: TWO (2) copies of your files on SEPARATE media - only counts when you have confirmed you have readable files on some other type of storage - a second and third HDD or SSD or Flash Drive or Cloud storage..

Once you are backed up, run your current AntiVIrus. Then consider running another AntiVirus ( https://www.pcmag.com/roundup/355173/the-best-mac-antivirus-protection ).

What do you find?

Thanks! I’m just trying to keep my old files safe when I backup everything into the same drive. The old files were from another computer, and I don’t want those files to get corrupted or infected.

 

[Cycloid Torus]

Failure of the storage media: crashing/mechanical or obsolescence or an unknown software issue or just being clumsiness means it is a good idea to have two copies.

 

[DelJo63]

OKAY; Kind of guessed that but need to certain.

In general, backups copy files (infected or not) onto the backup media. That exposes the user to any use of that backup CAN infect the system to which it is restored, so it is ABSOLUTELY necessary to ensure you system is clean before performing any kind of backup. You asked "how can I filter out infected files?" You CAN'T -- you need your A/V to clean the system first.

Time Machine:

• The first time Time Machine creates a backup on a target drive or for a target computer, it copies all files as a baseline.
• Subsequent backups only include changed files, and use a special hard link style of file pointer to make each snapshot look and act on disk as if it’s a full backup.
• Automatic snapshot deletion ensures at least one copy, always the most recent copy, of a file remains.
• see http://icanhelpyourmac.com/tip_archive/understanding_apples_time_machine/index.html

That says that even though there may be a clean version of file x in the Time Machine archive, the new snapshot will dominate the restore and reload any contaminated files, as they will be 'newer' than the originals.

New Subject: Infection upon mounting
If a virus is active on the SUBJECT system, it's impossible (externally like you & I) to tell HOW it propagates (sigh).
One of the old-time propagation techniques is to wait for a device to be "mounted" (internally, all systems use mount ) and your "attach" makes that happen. If a virus uses this technique, any infection it can perform occurs before the devices becomes visible on your desktop - - aka can't be defended.

Most newer virus' depend on Social Engineering to cause you to open a document/file or a link. These can be defended with A/V scanning.

 

[Peppermint]

OKAY; Kind of guessed that but need to certain.

In general, backups copy files (infected or not) onto the backup media. That exposes the user to any use of that backup CAN infect the system to which it is restored, so it is ABSOLUTELY necessary to ensure you system is clean before performing any kind of backup. You asked "how can I filter out infected files?" You CAN'T -- you need your A/V to clean the system first.

Time Machine:

• The first time Time Machine creates a backup on a target drive or for a target computer, it copies all files as a baseline.
• Subsequent backups only include changed files, and use a special hard link style of file pointer to make each snapshot look and act on disk as if it’s a full backup.
• Automatic snapshot deletion ensures at least one copy, always the most recent copy, of a file remains.

That says that even though there may be a clean version of file x in the Time Machine archive, the new snapshot will dominate the restore and reload any contaminated files, as they will be 'newer' than the originals.

New Subject: Infection upon mounting
If a virus is active on the SUBJECT system, it's impossible (externally like you & I) to tell HOW it propagates (sigh).
One of the old-time propagation techniques is to wait for a device to be "mounted" (internally, all systems use mount ) and your "attach" makes that happen. If a virus uses this technique, any infection it can perform occurs before the devices becomes visible on your desktop - - aka can't be defended.

Most newer virus' depend on Social Engineering to cause you to open a document/file or a link. These can be defended with A/V scanning.

Thanks! I think I’ll just run Malwarebytes, Sophos, and another antivirus software to make sure nothing is happening. Then, since I’ve never used Time Machine, just backup everything onto 2 drives and then just reset my laptop, ultimately destroying the virus/malware on the laptop. As for the drive, I’ll probably never use it unless it’s an emergency.

 

[DelJo63]

See http://icanhelpyourmac.com/tip_archive/understanding_apples_time_machine/index.html