600,000 Macs Worldwide Reportedly Infected by Flashback Trojan

apple security iconArs Technica reports on a Tweet from Russian malware analyst Ivan Sorokin at Dr. Web claiming that the Flashback trojan has now infected over 600,000 Macs worldwide. That number reportedly includes 274 machines "from Cupertino", presumably meaning at Apple's headquarters.

According to Dr. Web, the 57 percent of the infected Macs are located in the US and 20 percent are in Canada. Like older versions of the malware, the latest Flashback variant searches an infected Mac for a number of antivirus applications before generating a list of botnet control servers and beginning the process of checking in with them.

The authors of the Flashback trojan have continued to tweak the software since it first surfaced last September, adjusting its tactics several times to include both social engineering tricks and exploits of vulnerabilities.

The most recently-seen version of Flashback surfaced earlier this week, exploiting a Java vulnerability that was unpatched on OS X. While Oracle had released an update closing the hole on Windows back in February, Apple had yet to issue a fix for Macs, as the company has historically maintained its own Java updates that are deployed some time after Oracle issues its own corresponding updates. But just a day after that report, Apple did update Java to address the vulnerability being exploited by Flashback.

Antivirus firm F-Secure has instructions on how users can determine whether their machines are infected by the Flashback trojan. The instructions do involve running commands in Terminal, and users should thus take care to follow the instructions exactly.

Top Rated Comments

chrisperro Avatar
146 months ago
clean here, update your system often and you should not run into this trojans...
The malware self-installs after you visit a compromised or malicious webpage. Obviously, it would be a good idea to update any Macs in your control.

For those who want to check if mac is infected (from F-Secure instructions):
Run the following command in terminal:

defaults read /Applications/Safari.app/Contents/Info LSEnvironment
defaults read ~/.MacOSX/environment DYLD_INSERT_LIBRARIES

If you get "The domain/default pair ... does not exist" for both - you are clean


from 9to5mac
Score: 42 Votes (Like | Disagree)
basesloaded190 Avatar
146 months ago
I'm usually against cruel and unusual punishment, but people who spend their life creating these Trojans and other things need to be punished appropriately.
Score: 32 Votes (Like | Disagree)
Starflyer Avatar
146 months ago
If I'm reading the information on the F-secure website correctly, the trojan wont install itself if it discovers that Microsoft Office or Skype is already installed?

Interesting.
I guess it feels that we are suffering enough already with these installed. Hmm, this must be a new, more compassionate trojan.
Score: 29 Votes (Like | Disagree)
ArcaneDevice Avatar
146 months ago
Here comes the debate between the definitions of "Malware" and "Virus"

Humans can't get malware.
Score: 21 Votes (Like | Disagree)
miles01110 Avatar
146 months ago
People click through certificate warnings all the time, mostly because they don't know or care what it means. I don't think the scenario is as far-fetched as you seem to think it is.

Before going into panic mode, try to analyse what you have here. End user has to manually accept a self sign certificate from "Apple" for a Java application. One has to be very dumb to do that.

You cannot protect ignorant people, even if you like.

Difference here is that you only get infected if you explicitly allow malware to run. In MS world you get infected without even knowing it.
Score: 15 Votes (Like | Disagree)
davidcmc Avatar
146 months ago
Here we go again....

At least it appears to be easier to remove than a Windows style malware infection...
The article has clearly stated that you need to use Terminal, which involves commands and some deep knowledge of what you're doing, for Flashback's removal.
In Windows, you just need to use Windows Malicious Software Removal Tool or a decent anti-virus, which involves 1 or 2 clicks.

Yea, it's gotta be very hard to click things. I mean, typing commands in Terminal must be simpler.

I know that MacRumors is an Apple oriented place, where Apple lovers come to discuss things about Apple's product. But, posts like the one I quoted make it look like a fanboy place, not an Apple technology discussion place.
Score: 14 Votes (Like | Disagree)