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tiggle
Feb 18, 2007, 07:14 PM
I hope you don't mind me asking this question here. I know nothing about programming, but have been wondering about something. If I download malicious software written for Windows ( virus, adware etc,) on to my PPC running Mac OSX, what actually happens to it? Does it just sit there in my machine doing nothing? Can it infect files (word documents for example) that I may pass on to other machines?
Thanks in advance,
TIggle



iMeowbot
Feb 18, 2007, 07:22 PM
Does it just sit there in my machine doing nothing?
Yes, because the PowerPC simply can't execute x86 code, the binary formats for windows and OS X are different even on the same architecture, and in the general case even the scripting architectures for the two operating systems are completely different. So, even on an Intel Mac it would be hard for a Windows-targeted chunk o' malware to do much.

Can it infect files (word documents for example) that I may pass on to other machines?
If you open, for example, an infected Word document in Mac Word, that kind of infection can be cross-platform. Unless you're turned off the warnings, Office apps will tell you that there is scripting and let you decide how to proceed.

And of course, if you get an infected file from someone else and pass it along to someone else unchanged, it could affect the recipient even if it does nothing to you.

gnasher729
Feb 19, 2007, 10:34 AM
I hope you don't mind me asking this question here. I know nothing about programming, but have been wondering about something. If I download malicious software written for Windows ( virus, adware etc,) on to my PPC running Mac OSX, what actually happens to it? Does it just sit there in my machine doing nothing? Can it infect files (word documents for example) that I may pass on to other machines?

Various things can happen.

One thing that virus writers do is send you an email with an attachment that is a program, and then trick you somehow into running the program (for example, by calling it "britney_spears_naked.gif.exe so every idiot double-clicks it). If it is a program written for Windows, it just won't work. Of course if you forward that email to someone else, they might double-click it on a Windows PC and suffer the consequences. If someone did send you a MacOS X program, you could start it. MacOS X will give you quite a few warning messages, and anyone but a complete moron would _know_ that he/she is receiving a program.

The other thing that virus writers do is exploit bugs in software. For example, I send you a .gif picture. Some software in your computer will read the .gif file, turn it into graphics, and display it on the screen. That software might have bugs, and a virus writer could create a .gif file that exploits the bug. In that case, it is quite simple to crash the computer. It is very very difficult to exploit the bug in such a way that your computer does what the hacker wants. (It is like pushing your car off the road is not difficult. Pushing it off the road in such a way that it ends up in my garage without a scratch, that is difficult). Such exploits only work if the hacker knows _exactly_ what the software does, and it won't work against different versions of the software. As an example, some old Macintosh and Windows versions of Internet Explorer have identical bugs. If you visit certain websites, your Windows PC running Internet Explorer would get infected. A Macintosh running Internet Explorer with the same bug would just crash.

tiggle
Feb 19, 2007, 07:54 PM
Thanks very much for the replies. If I understand it then, a virus may do nothing at all, but may cause my machine to crash but not execute the hackers wishes. If my machine crashes, will this be a recuring problem or will it be solved on the next reboot?

Cheers again.

Jiddick ExRex
Feb 20, 2007, 06:47 AM
Thanks very much for the replies. If I understand it then, a virus may do nothing at all, but may cause my machine to crash but not execute the hackers wishes. If my machine crashes, will this be a recuring problem or will it be solved on the next reboot?

Cheers again.

If it exploits a picture rendering bug, it will only crash when you open the "image".

For it to be a continuing problem, one would have to write a script that you install and run it at login that displays said picture.

tiggle
Feb 20, 2007, 07:49 PM
Thanks so very much all. My questions must seem like common sense to you guys, so thanks for your patient and helpful remarks.
Cheers.