BitTorrent client is found distributing Mac-based malware

Months earlier, the Transmission BitTorrent client was found distributing Mac-based ransomware

A popular BitTorrent client called Transmission has again been found distributing Mac-based malware, months after it was used to spread a strand of ransomware.

Researchers at security firm ESET have been following a malware called OSX/Keydnap, which can steal passwords, and noticed that it was spreading through Transmission’s official site.

Somehow, a version of the BitTorrent client containing the malware had been recently made available on the site, ESET said in a blog post on Tuesday.

Transmission has already removed the download, according to ESET. But users who downloaded the client between this past Sunday and Monday should check for signs that their Mac has been comprised.

In addition to stealing credentials, the Keydnap malware functions as a backdoor program that can allow the hacker to execute remote commands on the Mac, including file downloads.

ESET published details on the malware in July, but the security firm wasn’t sure how it was being spread. “It could be through attachments in spam messages, downloads from untrusted websites, or something else,” the company said at the time.

Although Transmission didn’t immediately respond for comment, the developer is investigating the issue, according to ESET.  However, earlier this year, the BitTorrent client was also found spreading a Mac-based ransomware called KeRanger.

ESET noted the similarities between the two attacks.

“In both cases, a malicious block of code is added to the main function of the Transmission application,” ESET said. “The code responsible for dropping and running the malicious payload is astonishingly the same.”

Like KeRanger, the Keydnap malware was also spread through a Transmission client that was signed with a legitimate Apple developer’s certificate. This can help it bypass Apple’s malware detecting feature Gatekeeper.

While it isn't clear why Transmission was distributing the malware, its possible the site may have been hacked, and then uploaded with a tainted version of the BitTorrent client.

ESET has already notified Apple about the compromised developer certificate. The security firm’s products will also detect and remove the Keydnap malware.

Join the newsletter!

Error: Please check your email address.
Rocket to Success - Your 10 Tips for Smarter ERP System Selection
Keep up with the latest tech news, reviews and previews by subscribing to the Good Gear Guide newsletter.

Michael Kan

IDG News Service
Show Comments

Cool Tech

Breitling Superocean Heritage Chronographe 44

Learn more >

SanDisk MicroSDXC™ for Nintendo® Switch™

Learn more >

Toys for Boys

Family Friendly

Panasonic 4K UHD Blu-Ray Player and Full HD Recorder with Netflix - UBT1GL-K

Learn more >

Stocking Stuffer

Razer DeathAdder Expert Ergonomic Gaming Mouse

Learn more >

Christmas Gift Guide

Click for more ›

Most Popular Reviews

Latest Articles

Resources

PCW Evaluation Team

Walid Mikhael

Brother QL-820NWB Professional Label Printer

It’s easy to set up, it’s compact and quiet when printing and to top if off, the print quality is excellent. This is hands down the best printer I’ve used for printing labels.

Ben Ramsden

Sharp PN-40TC1 Huddle Board

Brainstorming, innovation, problem solving, and negotiation have all become much more productive and valuable if people can easily collaborate in real time with minimal friction.

Sarah Ieroianni

Brother QL-820NWB Professional Label Printer

The print quality also does not disappoint, it’s clear, bold, doesn’t smudge and the text is perfectly sized.

Ratchada Dunn

Sharp PN-40TC1 Huddle Board

The Huddle Board’s built in program; Sharp Touch Viewing software allows us to easily manipulate and edit our documents (jpegs and PDFs) all at the same time on the dashboard.

George Khoury

Sharp PN-40TC1 Huddle Board

The biggest perks for me would be that it comes with easy to use and comprehensive programs that make the collaboration process a whole lot more intuitive and organic

David Coyle

Brother PocketJet PJ-773 A4 Portable Thermal Printer

I rate the printer as a 5 out of 5 stars as it has been able to fit seamlessly into my busy and mobile lifestyle.

Featured Content

Product Launch Showcase

Latest Jobs

Don’t have an account? Sign up here

Don't have an account? Sign up now

Forgot password?