New 'Yontoo' Adware Trojan Targets Major Browsers on OS X

Russian security firm Doctor Web this week highlighted a new trojan (via The Next Web) affecting OS X systems and which installs an adware plug-in capable of injecting ads into users' browsing experience.

As with other trojans, this new Yontoo malware relies on tricking users into installing the package, which in this case masquerades as a movie trailer video plug-in, download accelerator, or other software a user might believe they want or need on their system.

When launched, Trojan.Yontoo.1 displays a dialogue window that asks the user if they want to install Free Twit Tube.

However, after the user presses ‘Continue’, instead of the promised program, the Trojan downloads (from the Internet) and installs the plugin Yontoo for Safari, Chrome and Firefox. These browsers are most popular among Mac OS X users. While a user surfs the web, the plugin transmits information about the loaded pages to a remote server.

In return, it gets a file that enables the Trojan to embed third-party code into pages visited by the user.

As an example of Yontoo's capabilities, Doctor Web shows how ads can be injected into apple.com once the plug-in has been unwittingly installed by the user.

apple_com_adware
Compared to Windows, OS X has long been a relatively unpopular target for malware authors, but attacks targeting Apple customers have been on the rise. Many of the most highly publicized attacks come via trojans that rely on tricking users into granting installation privileges, while third-party platforms such as Java have also frequently been used to inject code into Mac systems.

Apple has been increasing its efforts to fight malware, introducing a rudimentary anti-malware functionality in OS X Snow Leopard and an enhanced Gatekeeper system in OS X Mountain Lion. Apple has also increasingly been blocking vulnerable versions of Java until Oracle is able to release patched versions of its plug-ins.

Top Rated Comments

Slix Avatar
106 months ago
Want to install Free Twit Tube?

Seems legit. :rolleyes:
Score: 20 Votes (Like | Disagree)
litmag01 Avatar
106 months ago
Say YES to everything unless it asks to continue.

In that case, press CONTINUE and enter bank account number, routing number and any pertinant passwords.
Score: 18 Votes (Like | Disagree)
anzio Avatar
106 months ago
It's times like this that I'm glad that OS X has XProtect.

Oh yeah. And I'm happy I also wield common sense. :)
Score: 14 Votes (Like | Disagree)
Pechente Avatar
106 months ago
Wow, a user can be tricked to actively install harmful software - a serious flaw in OS X!
Score: 11 Votes (Like | Disagree)
Apple_Robert Avatar
106 months ago
Macs were never as secure as PCs but they were unpopular enough that nobody bothered to attempt to exploit them. Now it seems that every other day there's another massive security flaw found in Mac OS X.

What security flaw are you referring to with this story?
Score: 9 Votes (Like | Disagree)
vmistery Avatar
106 months ago
Macs were never as secure as PCs but they were unpopular enough that nobody bothered to attempt to exploit them. Now it seems that every other day there's another massive security flaw found in Mac OS X.

You missed patch Tuesday then?
Score: 9 Votes (Like | Disagree)

Top Stories

april 2021 event coverage feature

Apple Event Live Coverage: New iPads, AirTags, and More Expected [Event Over]

Tuesday April 20, 2021 9:07 am PDT by
Apple's virtual "Spring Loaded" event kicks off today at 10:00 a.m. Pacific Time, with Apple expected to debut updated iPad models and perhaps some other hardware such as AirTags or iMac models based on Apple silicon. Apple is providing a live video stream on its website, on YouTube, and in the company's TV app across its platforms. We will also be updating this article with live blog...
m1 imac colors

Apple Announces Redesigned iMac With M1 Chip and Seven Color Options

Tuesday April 20, 2021 10:22 am PDT by
Apple has announced a new, redesigned 24-inch iMac, featuring an M1 chip, a 4.5K display, and a range of color options, as well as an improved cooling system, front-facing camera, speaker system, microphones, power connector, and peripherals. The new iMac features a completely new compact design, and comes in a range of seven striking colors, including green, yellow, orange, pink, purple,...
duan rui iphone 12 13 notch

New Images Show Smaller iPhone 13 Notch Compared to iPhone 12

Saturday April 17, 2021 11:38 pm PDT by
Leaker known as "DuanRui" has shared more images that could give us our best look yet at Apple's redesigned notch for the iPhone 13. The new pictures follow similar images shared by the leaker last week, but the latest shots include a comparison with the existing iPhone 12 notch. DuanRui posted three images on Twitter that apparently originate from Weibo, although source details remain...
Top Stories 57 Feature

Top Stories: Apple Event Next Tuesday, Mini-LED iPad Pro, iPhone Rumors

Saturday April 17, 2021 6:00 am PDT by
It feels like we've been waiting forever for new Apple products, but the wait is almost over as Apple has announced a media event for next Tuesday, so make sure to tune into MacRumors for full coverage of everything Apple announces. While that was the big news this week, we also got some new details on Apple's iPhone plans for 2022 and 2023 courtesy of analyst Ming-Chi Kuo, and we also saw...
iphone 12 preorder purple

Apple Launching iPhone 12 and 12 Mini in New Purple Color on April 30

Tuesday April 20, 2021 10:08 am PDT by
Apple today announced that the iPhone 12 and iPhone 12 mini will be available in a new purple color starting April 30, with pre-orders starting this Friday. Apple is also releasing a new MagSafe Leather Case and Leather Sleeve in Deep Violet, a Silicone Case in Capri Blue, Pistachio, Cantaloupe, or Amethyst, and a Leather Wallet in Arizona, all available to order beginning today. iPhone...
f1618938547

Apple Announces AirTag Tracking Devices Starting At $29 Each

Tuesday April 20, 2021 10:10 am PDT by
Apple today announced AirTag, a Tile-like Bluetooth tracking device that's designed to be attached to items like keys and wallets for tracking purposes, letting you find them right in the Find My app. AirTags are accessories for attaching to backpacks, luggage, and other items. Any U1 device like the iPhone 12 can be used for precision finding to guide you right to the item you're looking...
iPad Pro

New 12.9-Inch iPad Pro Will Be 0.5mm Thicker to Accommodate Mini-LED Display

Monday April 19, 2021 11:30 am PDT by
The upcoming 12.9-inch iPad Pro will be thicker than the previous-generation version, likely due to the inclusion of the mini-LED display. We've heard several rumors about the change in thickness, and now leaked design images have confirmed it. A source that designs accessories for Apple devices sent MacRumors a series of photos that feature exact dimensions for the new iPad Pro models, and...
ipad pro with m1 chip

Apple Introduces Next-Generation iPad Pro With M1 Chip, Thunderbolt, 5G, XDR Display, and More

Tuesday April 20, 2021 10:40 am PDT by
Apple today announced the next-generation iPad Pro with the same M1 chip found in the latest Macs, Thunderbolt and USB4 support, 5G connectivity on cellular models with mmWave support in the United States, and more. With an 8-core CPU and 8-core GPU, Apple says the M1 chip in the new iPad Pro provides up to 50% faster performance and up to 40% faster graphics compared to the A12Z Bionic chip ...
iPad Pro Feature Orange

Wedbush Analysts Say 'Spring Loaded' Event Will Debut New iPads With 'Modest Price Increase,' Along With 'a Few Surprises'

Monday April 19, 2021 6:37 am PDT by
Apple is planning to launch a new entry-level iPad, iPad mini, and iPad Pro at its "Spring Loaded" event tomorrow, along with "a few surprises," according to Wedbush analysts. In a new note to investors, seen by MacRumors, Wedbush analysts Daniel Ives and Strecker Backe explained that the iPad will be the main focus of Apple's "Spring Loaded" event, with new entry-level iPad, iPad mini, and ...
flat imac 3d 3 teal

Reliable Leaker Hints Redesigned Colorful iMac to Debut at 'Spring Loaded' Event

Saturday April 17, 2021 4:43 am PDT by
Reliable leaker known as l0vetodream has hinted that Apple may debut its rumored redesigned and colorful iMac at its "Spring Loaded" event on Tuesday, April 20. In a tweet, the leaker posted an image of Apple's logo used for marketing the upcoming event and an image of the retro rainbow Apple logo alongside the colorful lineup of G3 iMacs. Apple leaker Jon Prosser previously reported that...