Apple Updates Anti-Malware Definitions to Address Fake Flash Player Trojan

flash player trojan
Fake Flash Player trojan installer

While things have been relatively quiet on the malware front for OS X since a raid on Russian payment processing firm ChronoPay appeared to have taken down MacDefender nearly two months ago, one new trojan horse did pop up earlier this month. As detailed by F-Secure, the trojan known as "OSX.QHost.WB.A" masquerades as a Flash Player installer but actually adds entries to a computer's hosts file to redirect users attempting to visit certain Google sites.

Once installed, the trojan adds entries to the hosts file to hijack users visiting various Google sites (e.g., Google.com.tw, Google.com.tl, et cetera) to the IP address 91.224.160.26, which is located in Netherlands.

The server at the IP address displays a fake webpage designed to appear similar to the legitimate Google site.

Search results on the fake Google pages actually lead to pop-up windows that load external content which was broken at the time of discovery but presumably consisted of advertisements of some sort. While the threat as implemented at the time of discovery was relatively mild, inexperienced users falling for the trojan could find themselves unaware of what had happened to their systems and how to fix the hijacked routing added by the malware.

osx qhost wb a
Consequently, Apple earlier this week made its first significant addition to its "XProtect.plist" file since the spate of MacDefender variants surfaced in June. The XProtect.plist file contains malware definitions to enable users' systems to recognize and warn users of malicious downloads, a feature that debuted with Mac OS X Snow Leopard back in 2009.

The original anti-malware system required manual updates to account for new threats, and as such was updated only rarely by Apple as part of larger software updates. But with an Apple software update issued in response to the MacDefender threat earlier this year, Mac OS X systems are now able to make daily checks for updates to that file to ensure up-to-date protection against malware.

Popular Stories

Generic iOS 19 Feature Mock Light

iOS 19 Leak Reveals All-New Design

Friday January 17, 2025 2:42 pm PST by
iOS 19 is still around six months away from being announced, but a new leak has allegedly revealed a completely redesigned Camera app. Based on footage it obtained, YouTube channel Front Page Tech shared a video showing what the new Camera app will apparently look like, with the key change being translucent menus for camera controls. Overall, the design of these menus looks similar to...
2024 App Store Awards

Apple Explains Why It Removed TikTok From the App Store in the U.S.

Sunday January 19, 2025 6:58 am PST by
Apple on late Saturday removed TikTok from the App Store in the U.S., and it has now explained why it was required to take this action. Last year, the U.S. passed a law that required Chinese company ByteDance to divest its ownership of TikTok due to potential national security risks, or else the platform would be banned. That law went into effect today, and companies like Apple and Google...
iPhone SE Dynamic Island Majin Bu

iPhone SE 4 Leak Shows Dynamic Island, Casts Doubt on Rumored 'iPhone 16E' Name

Monday January 20, 2025 9:01 am PST by
A new iPhone SE is widely rumored to launch this year, and the device has potentially been confirmed today by known leaker Evan Blass. In a private social media post, Blass shared an image of what appears to be source code mentioning an iPhone SE (4th Gen), which casts doubt on the alternative "iPhone 16E" name rumored for the device. However, the name in the source code could be a...
iOS 19 Roundup Feature

iOS 19 Rumored to Be Compatible With These iPhones

Saturday January 18, 2025 10:28 am PST by
iOS 19 will not drop support for any iPhone models, according to French website iPhoneSoft.fr. The report cited a source who said iOS 19 will be compatible with any iPhone that can run iOS 18, which would mean the following models: iPhone 16 iPhone 16 Plus iPhone 16 Pro iPhone 16 Pro Max iPhone 15 iPhone 15 Plus iPhone 15 Pro iPhone 15 Pro Max iPhone 14 iPhon...
airtag 4 pack blue

AirTag 2 Launching This Year With These 3 New Features

Sunday January 19, 2025 8:11 am PST by
After a four-year wait, a new AirTag is finally expected to launch in 2025. Below, we recap rumored upgrades for the accessory. A few months ago, Bloomberg's Mark Gurman said Apple was aiming to release the AirTag 2 around the middle of 2025. While he did not offer a more specific timeframe, that means the AirTag 2 could be announced by the end of June. The original AirTag was announced...
iPhone 17 Air Size Feature

'iPhone 17 Air' With Rear Camera Bar Allegedly Shown in Leaked Photo

Tuesday January 21, 2025 12:46 pm PST by
A leaker known as "Majin Bu" today shared an alleged image of a component for the rumored, ultra-thin "iPhone 17 Air" model. The blurry, pixelated image shows a pair of rear iPhone shells with a pill-shaped, raised camera bar along the top. On the left side of the bar, there is a circular cutout that appears to be for a single rear camera. On the right side of the bar, there appears to be an ...
apple power beats pro 2

Powerbeats Pro 2 Coming Soon: Apple to Announce Them 'Imminently'

Sunday January 19, 2025 8:25 am PST by
In September, Apple said that it would be launching Powerbeats Pro 2 in 2025, and it appears the wireless earbuds are coming very soon. Powerbeats Pro 2 images found in iOS 18 code In his Power On newsletter today, Bloomberg's Mark Gurman said the Powerbeats Pro 2 are "due imminently." In addition to Apple filing the Powerbeats Pro 2 in regulatory databases last month, Gurman said Apple is...
Generic iOS 18

Everything New in iOS 18.3 Beta 3

Thursday January 16, 2025 12:39 pm PST by
Apple provided the third beta of iOS 18.3 to developers today, and while the betas have so far been light on new features, the third beta makes some major changes to Notification Summaries and also tweaks a few other features. Notification Summary Changes Apple made multiple changes to Notification Summaries in response to complaints about inaccurate summaries of news headlines. For...

Top Rated Comments

KnightWRX Avatar
176 months ago
Let's get this out of the way right now : This is not an OS X virus.
Score: 36 Votes (Like | Disagree)
Stridder44 Avatar
176 months ago
Awesome, I was not aware that it updated daily.

And yes, this is not a virus. This is malware.
Score: 11 Votes (Like | Disagree)
longofest Avatar
176 months ago
No, it's not a "virus". It's a trojan. You think it's good, but its bad. (heh... depending on if you think "flash" is "good").

A question I have though, is under what conditions should ANY software modify the hosts file? Should Apple even allow programs that have been granted administrative rights to alter the hosts file? There is only a very limited benvolent use case for such an action, and that very related to what they did here: some anti-ad or anti-spyware utilities modify a host file to redirect known ad-producing domains to a "safe" domain. I personally think any modification of the host file should be given a warning like this:

The program _____ is trying to update a core Mac OS X system file that is used to provide network connectivity. While online advertisement blocking programs may require legitimate use of this file, most others applications may represent an attempt to install malicious software onto your computer. Are you sure you want to allow program _____ to modify this file?
Score: 9 Votes (Like | Disagree)
BC2009 Avatar
176 months ago
Funny.... I updated Flash yesterday on my kids' Mac mini and I thought that writing a Trojan that masquerades as an update to Flash would be brilliant since Flash is updated so often and getting prompted that you need to update Flash to view a website is very common..... And then today, here it is.
Score: 8 Votes (Like | Disagree)
Sjhonny Avatar
176 months ago
That's why you need to disable flash. :p

This has nothing to do with Flash.
Score: 8 Votes (Like | Disagree)
devilstrider Avatar
176 months ago
Been out of the loop for 10 weeks and MacRumors is getting my up to speed fast. I love this site.
Score: 8 Votes (Like | Disagree)