Apple Addresses 'Mac Defender' Threat With Security Update 2011-003 for Snow Leopard - MacRumors
Skip to Content

Apple Addresses 'Mac Defender' Threat With Security Update 2011-003 for Snow Leopard

by

macdefender
Apple today released Security Update 2011-003 (Snow Leopard), a new software update that addresses the "Mac Defender" malware that has been afflicting Mac users over the past month.

- Malware removal

Available for: Mac OS X v10.6.7, Mac OS X Server v10.6.7

Impact: Remove the MacDefender malware if detected

Description: The installation process for this update will search for and remove known variants of the MacDefender malware. If a known variant was detected and removed, the user will be notified via an alert after the update is installed.

The update weighs in at 2.36 MB and requires Mac OS X 10.6.7.

Seed notes for the most recent developer build of Mac OS X 10.6.8 had indicated that the update will identify and remove known variants of Mac Defender, but Apple apparently wanted to push the anti-malware portions of the update as quickly as possible before incorporating it directly into Mac OS X 10.6.8 for future updaters.

Popular Stories

Dynamic Island iPhone 18 Pro Feature

11 Reasons to Wait for the iPhone 18 Pro

Monday May 11, 2026 9:01 am PDT by
We're only four months out from the launch of Apple's premium next-generation smartphone lineup, and while we're not expecting a sea change in terms of functionality, there are still several enhancements rumored to be coming to the iPhone 18 Pro and iPhone 18 Pro Max. One thing worth noting is that Apple is reportedly planning a major change to its iPhone release cycle this year, adopting a...
Read Full Article • 35 comments
General Apps Reddit Feature

Reddit Starts Blocking Mobile Website, Pushing Users to App Instead

Monday May 11, 2026 6:10 am PDT by
Social network Reddit recently began blocking mobile visitors to its website while pushing them to download the official Reddit app, and it's fair to say that the move is not going down well with users. If you visit reddit.com on your iPhone today, you may see a new popup that can't be dismissed, asking you to "get the app to keep using Reddit." A Reddit spokesperson told Ars Technica...
Read Full Article • 124 comments
iOS 26

iOS 26.5 Features: Everything New in iOS 26.5

Monday May 11, 2026 5:09 pm PDT by
Apple released iOS 26.5 after a few months of beta testing, and while it doesn't have the Siri features we were hoping for since those are being held until iOS 27, there are a handful of useful changes worth knowing about. Subscribe to the MacRumors YouTube channel for more videos. End-to-End Encryption for RCS Support for end-to-end encryption (E2EE) for RCS messages between iPhone and...
Read Full Article • 57 comments

Top Rated Comments

C
Cougarcat
195 months ago
While i dont know the actual threat of his particular 'malware', I think apple needs to do a lot better than this in future. Such hot fixes need to be available within a couple of days max. If i wanted to use a virus/malware prone PC for weeks, i'd have simply opted for a windows machine instead of the mac!

And it should be available for 10.5 as well.
Score: 13 Votes (Like | Disagree)
M
MacMan86
195 months ago
While i dont know the actual threat of his particular 'malware', I think apple needs to do a lot better than this in future. Such hot fixes need to be available within a couple of days max. If i wanted to use a virus/malware prone PC for weeks, i'd have simply opted for a windows machine instead of the mac!
Apple have just made the very sensible step of allowing auto-updating of their malware definitions list. Future malware shouldn't require a formal Software Update:

"File Quarantine

Available for: Mac OS X v10.6.7, Mac OS X Server v10.6.7

Impact: Automatically update the known malware definitions

Description: The system will check daily for updates to the File Quarantine malware definition list. An opt-out capability is provided via the "Automatically update safe downloads list" checkbox in Security Preferences. Additional information is available in this Knowledge Base article: http://support.apple.com/kb/HT4651"
From http://support.apple.com/kb/HT4657
Score: 8 Votes (Like | Disagree)
Chris Grande Avatar
Chris Grande
195 months ago
This security update also makes the system automatically and in the background update the File Quarantine definitions daily.
Score: 6 Votes (Like | Disagree)
benthewraith Avatar
benthewraith
195 months ago
Nope. Just Windows ME.

It's not that you find viruses on Windows ME computers. It's that Windows ME IS a virus.
Score: 5 Votes (Like | Disagree)
tkermit Avatar
tkermit
195 months ago
Nice! :)

Score: 4 Votes (Like | Disagree)
blackburn Avatar
blackburn
195 months ago
There are exploits for mac os x, linux and windows. It's just a gamble, and you might get hacked in either systems. If the mac user base continues to grow we should expect more malware.

The best protection is to be smart, and be careful to with the sites you visit.
Score: 3 Votes (Like | Disagree)
Read All Comments