Why are there no viruses for OS X
July 2nd, 2009, Hedi Regaya | View Comments

Why there are no viruses for OS X?
- OS X is built on UNIX. UNIX was a multi user system with a security architecture built into it at the beginning. WINDOWS came from a single user architecture with security and multi user capability as an after thought.
- UNIX had networking built into it from the beginning, again in Windows this was bolted in at a later date.
- Windows built Internet Explorer into the O/S at a very deep level, and allowed code execution within the browser. In OS X the browser is a completely separate application, its not a integral part of the OS. IMHO, this is the fundamental screw-up Microsoft made, as they created so many hooks into which someone can attack the OS.
- In earlier Windows everything ran as the system user, so the capability to compromise an entire system was easier. (see reason 1)
- Microsoft’s backward compatibility mantra doesn’t do them any favours as to run old software they need so many old APIs, all of which can have holes in them.
- OS X has no registry. IMHO, second fundamental flaw Microsoft made.
- OS X asks for your password before allowing you to run new software or install something. Not fool proof, but at least fool resistant.
- Where do viruses usually hang out in Windows:
1. At the root.
2. In the user’s local settings temp folder.
3. In these folders: \windows, \system, \system32 — the most common places where I find viruses.
4. As registry entries.
None of those areas are exposed to the environment in OS X. You can’t see those folders. Virus writers can’t access them. Thus, viruses can’t exploit those areas. Vista’s UAC is MS’s attempt to prevent changes to those totally exposed folders without your being aware of the changes.
Posted in Mac OS X, Security & Maintenance















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I really enjoyed your post explaining why there are no viruses for Macs, and I have blogged about it today at TheMacLawyer.com. Keep up the good work.
I said it and said it so many times!
yes you are right.
“one” of the problems we as mac users face at the present is “packages” and the flaws involved with them.
one is “dmg” and “zip”.
a hidden script could be written to modify or destroy things in the users
PATH.
the so-called good thing is that the system would be fine, just the users account is effected (still not good)
make sure you at least enable “secure virtual memory” and write a script that deletes the stale cache in those funny places.
virus’s have it bad yes, but bad hackers no.
disable “webserver, screen sharing and SMB sharing” if your not using it.
turn off “open safe files after downloading” in safari.
these can and will be used against you.
that would at least keep the little kids out