New Variant of 'Mac Defender' Quickly Evades Apple's Security Update as Cat-and-Mouse Game Begins

macdefender dialog box
As we noted yesterday, Apple released Security Update 2011-003 for Mac OS X Snow Leopard, a system update addressing the "Mac Defender" malware threat that has been running in the wild under several different variants for the past month. The update provides tools for automatically removing the malware, as well as protection against future infections. But as reported by ZDNet, a new variant of the malware capable of circumventing Apple's update has already appeared. popping up within hours of Apple's software release.

Hours after Apple released this update and the initial set of definitions, a new variation of Mac Defender is in the wild. This one has a new name, Mdinstall.pkg, and it has been specifically formulated to skate past Apple's malware-blocking code.

The file has a date and time stamp from last night at 9:24PM Pacific time. That's less than 8 hours after Apple’s security update was released.

Apple has prepared for this eventuality by including automatic daily updates of malware definitions with the software update, enabling it to quickly deploy protection as new variants and entirely different pieces of malware surface. Consequently, Apple should be able to respond to the new threat relatively quickly, although the speed with which the new variant appeared suggests that those responsible for the malware will not be going away easily.

Top Rated Comments

laurim Avatar
133 months ago
I'm amazed people are still stupid enough to manually download and run this considering all the press coverage it has received.
I'm amazed people have nothing better to do than create viruses and malware all day. Imagine what could be achieved if people used their time and skills to do something useful for society. Hope they goof up, get traced and held accountable.
Score: 35 Votes (Like | Disagree)
chrono1081 Avatar
133 months ago
Props to those guys beating Apple at this.

As much as you can hate windows, MS has been very serious about security on Windows with a much tighter security system in Windows 7. Not saying that they had already not needed that, but they have been very careful and have come strong on viruses and malware.

Apple, you need to tighten up here.

Nice troll attempt. If MS was serious about security they would start by removing the registry.
Score: 19 Votes (Like | Disagree)
Popeye206 Avatar
133 months ago
LOL! Funny.... looks like the crooks are hard at work to stir the pot on the Mac side.

Doesn't scare me. I don't install what I don't know. Malware is just annoying.
Score: 19 Votes (Like | Disagree)
Popeye206 Avatar
133 months ago
Props to those guys beating Apple at this.

As much as you can hate windows, MS has been very serious about security on Windows with a much tighter security system in Windows 7. Not saying that they had already not needed that, but they have been very careful and have come strong on viruses and malware.

Apple, you need to tighten up here.

The thing is, Malware is user initiated. Unless MS, Apple or whoever knows about a specific threat, you can't stop someone from offering a user the opportunity to download something. If they say yes, they invite the crooks in. Viruses is another story. These have to go around security in the OS to install themselves and extract information or change system settings to cause harm. Obviously the second is way more dangerous because you don't see it coming.

I only point this out because what the heck is Apple suppose to do any different? If you don't know what to not allow, or look for, you can't stop someone from wanting to install software.
Score: 16 Votes (Like | Disagree)
Popeye206 Avatar
133 months ago
Makes you wonder if nokia/ms are behind this! :)

LOL!

I've always wondered is the Virus protection companies aren't the ones that hire suspect engineers from places like Russia to keep the need for them rolling. Wouldn't be too surprising if it was true.
Score: 14 Votes (Like | Disagree)
BaldiMac Avatar
133 months ago
Props to those guys beating Apple at this.

As much as you can hate windows, MS has been very serious about security on Windows with a much tighter security system in Windows 7. Not saying that they had already not needed that, but they have been very careful and have come strong on viruses and malware.

Apple, you need to tighten up here.

What is Microsoft doing that Apple is not that would currently prevent a Mac Defender type attack? Daily definition updates of an anti-malware scanner is the most appropriate strategy. Outside of preventing the user from installing unapproved applications, I'm not sure what else you can do.
Score: 14 Votes (Like | Disagree)

Top Stories

Pro Display XDR Yella

Apple Working on External Display With Built-In A13 Chip

Friday July 23, 2021 9:37 am PDT by
Apple is developing an external display that includes an A13 chip with Neural Engine, according to a new rumor from 9to5Mac. The A13 chip with Neural Engine would presumably serve as an eGPU, though details are light at this time. Having a CPU/GPU built into the external display could help Macs deliver high-resolution graphics without using all the resources of the computer's internal chip....
iOS 14 on iPhone feature emergency

Apple Releases iOS and iPadOS 14.7.1 With Fix for Touch ID Apple Watch Bug

Monday July 26, 2021 9:48 am PDT by
Apple today released iOS and iPadOS 14.7.1, minor bug fix updates that come just a week after the release of iOS 14.7, software that introduced new Apple Card features and support for the MagSafe Battery Pack. The iOS and iPadOS 14.7.1 updates can be downloaded for free and the software is available on all eligible devices over-the-air in the Settings app. To access the new software, go to...
discount m1 macbook yellow

Deals: Shop Record Low Prices Across Apple's Full MacBook Pro and MacBook Air Lineup (Up to $499 Off)

Friday July 23, 2021 8:23 am PDT by
Apple's MacBook Pro and MacBook Air lineup is seeing all-time low discounts across the board today, including the 2019 16-inch MacBook Pro, 2020 13-inch MacBook Air, and 2020 13-inch MacBook Pro. Note: MacRumors is an affiliate partner with some of these vendors. When you click a link and make a purchase, we may receive a small payment, which helps us keep the site running. 13-Inch M1...
iphone 12 pro gold

Report: iPhone 14 Pro Models to Feature Tough Titanium Alloy Chassis

Monday July 26, 2021 1:12 am PDT by
Next year's "iPhone 14" series is expected to feature high-end models with a new titanium alloy chassis design, claims a new investors report by JP Morgan Chase. According to the report, the use of titanium alloy will be one of the biggest changes to the case design in the 2022 iPhone series, and Foxconn will be the exclusive manufacturer of the titanium frames for the high-end models....
FaceID iMac REREREREMIX

Gurman: Face ID on the Mac Coming Within a 'Couple of Years'

Sunday July 25, 2021 7:09 am PDT by
Apple plans to bring Face ID to the Mac within the next "couple of years," respected Bloomberg journalist Mark Gurman said today in the latest edition of his Power On newsletter. In the newsletter, Gurman says that he believes Apple's ultimate goal is to shift all of its products to Face ID, including the lower-end iPhones such as the iPhone SE and the iPad Air, which feature Touch ID....
airpods 3 gizmochina Feature

AirPods 3 Rumored to Launch Alongside iPhone 13 at Expected September Event

Friday July 23, 2021 12:54 am PDT by
The third-generation AirPods will likely launch at the same event revealing Apple's upcoming iPhone 13 lineup, according to a report from DigiTimes, which makes the claim citing sources familiar with the matter. The report as a whole echoes previous reporting that production of the third-generation AirPods will kickstart in August, meaning a launch shortly after can be easily expected. DigiTi...
imac with accessories

Larger Redesigned High-End iMac Rumored to Launch Next Year

Monday July 26, 2021 3:45 am PDT by
Apple's larger redesigned iMac will arrive sometime in 2022 rather than later this year, according to the leaker known as "Dylandkt." On Twitter, Dylandkt claimed that Apple's "high end iMac" is not expected to release in the fourth quarter of 2021 alongside Apple's "M1X Macs" – a reference to Apple's redesigned MacBook Pro models – because "Apple simply does not want their devices to...
apple bitcoin hack

Is Apple Really Buying Bitcoin?

Monday July 26, 2021 3:07 am PDT by
A large number of websites and posts on social media are stoking rumors that Apple has purchased $2.5 billion worth of bitcoin in the company's first move into cryptocurrency, but is there any validity to the claims? Many people are citing the fact that Apple was looking for a Business Development Manager with experience in alternative payments, including cryptocurrency, earlier this year as ...
apple mac business page

Apple Shares 11 Reasons Why Business Users Should Choose Macs

Monday July 26, 2021 11:35 am PDT by
Apple today updated its Apple at Work website with a new section dedicated to the Mac, which offers up 11 reasons why "Mac means business." On the webpage, Apple highlights the M1 chip as the number one reason why business users should choose a Mac, offering up an M1 overview [PDF] that explains the benefits of the M1 chip. The information isn't new, but it does provide a look at all of...
magsafe battery pack iphone 12 mini

Top Stories: Hands-On With MagSafe Battery Pack, iPhone 13 Always-On Display?

Saturday July 24, 2021 6:00 am PDT by
Apple's new MagSafe Battery Pack is now available, and we went hands-on this week for some early impressions of the new accessory to get more battery life out of Apple's iPhone 12 lineup. Subscribe to the MacRumors YouTube channel for more videos. This week also saw a number of rumors about the upcoming redesigned MacBook Pro models, the iPhone 13 lineup, the next-generation iPad mini, a new...