twitter ios iconWe've been following for some time the story of the Flashback trojan that has been targeting Mac users by masquerading as a Flash Player installer but which has also been evolving to include increasingly sophisticated tactics for infecting users' computers.

Antivirus firm Intego now reports that Flashback's creators are using an interesting new tactic for communicating with machines infected by the trojan: Twitter. According to the report, Flashback is programmed to search Twitter for Tweets containing a unique 12-digit code that changes daily, with the malware's authors being able to issue commands to infected computers by posting from any number of Twitter accounts simply by including the appropriate code as a hashtag.

These hashtags aren’t as simple as, say, #Flashback or #MacMalwareMaster, but are seemingly random strings of characters that change each day. Intego’s malware research team cracked the 128-bit RC4 encryption used for Flashback’s code and discovered the keys to this system.

The hashtags are made up of twelve characters. There are four characters for the day, four characters for the month, and four characters for the year. [...]

So, for today, March 5, 2012, the hashtag would be #pepbyfadxeoa.

Intego is monitoring Twitter to look for any commands being issued using the hashtag codes, also noting that Flashback uses a number of different user agent strings in its web queries looking for the Twitter contacts, seeking to avoid detection and removal.

Top Rated Comments

GGJstudios Avatar
157 months ago
I just upgraded my gfs flashplayer last week ... What are the chances that it's this Trojan ?? How can I check?
Go to your /Users/yourusername/Library/ folder and look to see if you find any of these files:
~/.MacOSX/environment.plist
~/Library/LaunchAgents/com.apple.SystemUI.plist
~/Library/Preferences/perflib
~/Library/Preferences/Preferences.dylib
~/Library/Logs/swlog
If you don't have any of these files, you're not infected.

Your Library folders are hidden by default in Lion. To get to your /Library or /Users/yourusername/Library (also known as the ~/Library) folders in Lion, Launch Finder and click Go > Go to Folder and type: /Library or ~/Library

Here's how to avoid any question:
With my flash player I'm careful. I never click on a pop-up when it tells me it's out of date.

I go to Adobe's site and update there.
This is very important:
To repeat: the vendor has provided no actual evidence that such messages are happening.
In fact, while I may have missed it, I've seen no corroborating evidence supporting the recent reports coming from Intego. I haven't seen any other security firm confirming the presence of these variations, or the variation that supposedly installs itself without user intervention, as they also claim. Until such claims are proven by other companies, I'll continue to find Intego's claims suspicious, at best.

Generally speaking, these reports by security firms are little more than thinly veiled attempts to scare users into buying their security software, which you don't need. However, such reports can be useful reminders for users to continue to practice safe computing.
[LIST=1]
* Make sure your built-in Mac firewall is enabled in System Preferences > Security > Firewall


* Uncheck "Open "safe" files after downloading" in Safari > Preferences > General


* Uncheck "Enable Java" in Safari > Preferences > Security. Leave this unchecked until you visit a trusted site that requires Java, then re-enable only for your visit to that site. (This is not to be confused with JavaScript, which you should leave enabled.)


* Check your DNS settings by reading this (https://guides.macrumors.com/Mac_Virus/Malware_FAQ#Why_am_I_being_redirected_to_other_sites.3F).


* Be careful to only install software from trusted, reputable sites. Never install pirated software. If you're not sure about an app, ask in this forum before installing.


* Never let someone else have physical access to install anything on your Mac.


* Always keep your Mac and application software updated. Use Software Update for your Mac software. For other software, it's safer to get updates from the developer's site or from the menu item "Check for updates", rather than installing from any notification window that pops up while you're surfing the web.

That's all you need to do to keep your Mac completely free of any virus, trojan, spyware, keylogger, or other malware.

You don't need any 3rd party antivirus app to keep your Mac malware-free. Macs are not immune to malware, but no true viruses exist in the wild that can run on Mac OS X, and there never have been any since it was released over 10 years ago. You cannot infect your Mac simply by visiting a website, unzipping a file, opening an email attachment or joining a network. The only malware in the wild that can affect Mac OS X is a handful of trojans, which cannot infect your Mac unless you actively install them, and they can be easily avoided with some basic education, common sense and care in what software you install. Also, Mac OS X Snow Leopard and Lion have anti-malware protection (http://support.apple.com/kb/ht4651) built in, further reducing the need for 3rd party antivirus apps.
Mac Virus/Malware FAQ (https://guides.macrumors.com/Mac_Virus/Malware_FAQ)
Score: 8 Votes (Like | Disagree)
FloatingBones Avatar
157 months ago
The claim is interesting, but a quick search on Twitter doesn't show that #pepbyfadxeoa is actually being used by any program for anything. If the vendor's claim is true, they should be able to tell us a prior hashtag which shows actual nefarious activity.

We are still suffering from Adobe's lax attitudes for security around their products. All of the "Get Flash Player" and "Get Adobe PDF Reader" links that Adobe encouraged in the past have helped foster a lackadaisical attitude towards the clear risk of installing a trojan horse on machines. I will be happy as Flash on the WWW continues to fade into the sunset.

I think this uses twitter even if you don't use it personally, they are just using the open nature of the site as a means to communicate with the malware.
Bingo. If the trojan is actually using twitter as a conduit, it's probably using accounts that were embedded in the trojan. Blocking those would require the blocking of connections to twitter servers with something like Little Snitch (http://www.obdev.at/products/littlesnitch/index.html)
or outbound blocks in your network's firewall.

To repeat: the vendor has provided no actual evidence that such messages are happening. I see no evidence with todays hashtag.

One other note: the Twitter stream is a real cesspool these days. As far as I can tell, Twitter does nothing to automatically remove the 'bot accounts that send out Amazon Associates link-spam. They're also doing nothing to automatically censor accounts that send @mentions that spam the "adult" dating sites. Doesn't Twitter have any friends in the Valley who could help them keep the toxic pollution out of their stream?
Score: 7 Votes (Like | Disagree)
GGJstudios Avatar
157 months ago

Much like life, if you hang around in bars, you can come down with diseases.
So if you don't hang around in bars, you won't catch any diseases???
Score: 6 Votes (Like | Disagree)
FloatingBones Avatar
157 months ago
I'm always suspicious of anti-virus firms who seem to know very specific details of viruses/malware/trojans.

I'm even more suspicious when the claimed evidence doesn't pan out. To alter the slogan from that famous Wendy's commercial (//www.youtube.com/watch?v=Ug75diEyiA0):

Where's the tweets? :D
Score: 5 Votes (Like | Disagree)
mijail Avatar
157 months ago
I'm always suspicious of anti-virus firms who seem to know very specific details of viruses/malware/trojans.

Word, bro. And what about those pesky "doctors" who seem to know all about illnesses and bacteria and whatnot? Damned scientists!
(Fricking magnets, how do they work?)

----------

Then you can send a message to the hacker how dumb he was. With the same amount of work he had put into this malware he could have created an app and probably made some money.

You mean he has no bussiness plan for this?
Score: 4 Votes (Like | Disagree)
Amazing Iceman Avatar
157 months ago
Nasty!!

(I'm breaking my arm patting myself on the back for my non-involement with social media.)

I do feel bad for the majority of the world who does use social media...this is really lousy.

Much crap on social media, but a tremendous amount of good in places where free expression is only possible through Twitter, etc. It's a powerful tool for many in the world, and any sympathy I might have for certain hackers is totally absent in situations like this.

Well, don't over pad yourself. The infection doesn't come from Twitter, but from a fake Adobe Flash Installer. Twitter is only one of the many ways hackers use to communicate with the hacked Macs.
Score: 3 Votes (Like | Disagree)

Popular Stories

reset password request iphone

Warning: Apple Users Targeted in Phishing Attack Involving Rapid Password Reset Requests

Tuesday March 26, 2024 4:34 pm PDT by
Phishing attacks taking advantage of Apple's password reset feature have become increasingly common, according to a report from KrebsOnSecurity. Multiple Apple users have been targeted in an attack that bombards them with an endless stream of notifications or multi-factor authentication (MFA) messages in an attempt to cause panic so they'll respond favorably to social engineering. An...
Generic iOS 18 Feature Purple

iOS 18: What to Expect From 'Biggest' Update in iPhone's History

Wednesday March 27, 2024 11:10 am PDT by
At least some Apple software engineers continue to believe that iOS 18 will be the "biggest" update in the iPhone's history, according to Bloomberg's Mark Gurman. Below, we recap rumored features and changes for the iPhone. "The iOS 18 update is expected to be the most ambitious overhaul of the iPhone's software in its history, according to people working on the upgrade," wrote Gurman, in a r...
maxresdefault

Apple Announces WWDC 2024 Event for June 10 to 14

Tuesday March 26, 2024 10:02 am PDT by
Apple today announced that its 35th annual Worldwide Developers Conference is set to take place from Monday, June 10 to Friday, June 14. As with WWDC events since 2020, WWDC 2024 will be an online event that is open to all developers at no cost. Subscribe to the MacRumors YouTube channel for more videos. WWDC 2024 will include online sessions and labs so that developers can learn about new...
apple maps 3d feature

Apple Maps May Gain Custom Routes With iOS 18

Tuesday March 26, 2024 3:10 pm PDT by
Apple may be planning to add support for "custom routes" in Apple Maps in iOS 18, according to code reviewed by MacRumors. Apple Maps does not currently offer a way to input self-selected routes, with Maps users limited to Apple's pre-selected options, but that may change in iOS 18. Apple has pushed an iOS 18 file to its maps backend labeled "CustomRouteCreation." While not much is revealed...
General iOS 17 Feature Orange Purple

Apple Releases Revised Versions of iOS 17.4.1 and iPadOS 17.4.1 With Updated Build Number

Wednesday March 27, 2024 5:59 am PDT by
Apple on late Tuesday released revised versions of iOS 17.4.1 and iPadOS 17.4.1 with an updated build number of 21E237, according to MacRumors contributor Aaron Perris. The updates previously had a build number of 21E236. The revised updates are available for all iPhone and iPad models that are compatible with iOS 17 and iPadOS 17, but they can only be installed via the Finder app on macOS...
applephilschiller

Apple's Phil Schiller Works 80 Hours a Week Overseeing App Store

Wednesday March 27, 2024 2:03 pm PDT by
With the App Store and app ecosystem undergoing major changes in the European Union, The Wall Street Journal today shared a profile on App Store chief Phil Schiller, who is responsible for the App Store. Though Schiller transitioned from marketing chief to "Apple Fellow" in 2020 to take a step back from Apple and spend more time on personal projects and friends, he is reportedly working...
maxresdefault

Apple to Launch New iPad Pro and iPad Air Models in May

Thursday March 28, 2024 11:07 am PDT by
Apple will introduce new iPad Pro and iPad Air models in early May, according to Bloomberg's Mark Gurman. Gurman previously suggested the new iPads would come out in March, and then April, but the timeline has been pushed back once again. Subscribe to the MacRumors YouTube channel for more videos. Apple is working on updates to both the iPad Pro and iPad Air models. The iPad Pro models will...
iphone 16 dummies

iPhone 16 Dummy Models Showcase Design Changes, New Buttons

Tuesday March 26, 2024 6:03 am PDT by
Images comparing purportedly accurate dummy models of the iPhone 16 series have been shared online, providing a closer look at the rumored design of the upcoming devices. The iPhone 16 Pro and iPhone 16 Pro Max are expected to get larger display sizes this year, according to multiple sources, while the iPhone 16 and iPhone 16 Plus will be the same size as the iPhone 15 and iPhone 15 Plus. ...