First Mac Ransomware Found in Transmission BitTorrent Client

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This weekend, a notice appeared on Transmissionbt.com warning users that version 2.90 of the popular Mac BitTorrent client downloaded from their site may have been infected with malware. The warning reads:

Everyone running 2.90 on OS X should immediately upgrade to 2.91 or delete their copy of 2.90, as they may have downloaded a malware-infected file.

Using “Activity Monitor” preinstalled in OS X, check whether any process named “kernel_service” is running. If so, double check the process, choose the “Open Files and Ports” and check whether there is a file name like “/Users//Library/kernel_service”. If so, the process is KeRanger’s main process. We suggest terminating it with “Quit -> Force Quit”

Reuters reports that the infected download contained the first "Ransomware" found on the Mac platform. Ransomware is a type of malware that encrypts a user's hard drive and demands payment in order to unencrypt it. This type of attack has been increasingly popular on the PC, but this is the first time it has been seen on the Mac.

According to Reuters, Apple is aware of the issue and has already revoked "a digital certificate from a legitimate Apple developer that enabled the rogue software to install on Macs."

The malware in question is said to delay encrypting the user's hard drive for 3 days, so we may see the first reports of those affected as early as Monday. Transmissionbt.com offers instructions on how to see you are affected (above). If you don't use the Transmission software, there is nothing you need to do at this time.

Update: Technical details about the malware.

Update 2: Transmissionbt.com says version 2.92 of Transmission will actively remove the malware.

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Top Rated Comments

stridemat Avatar
126 months ago
to be expected when people use BitTorrent, I have zero sympathy for people who pirate stuff!
Whilst most the time both go hand in hand, BitTorrent is just a method of file transfer and not directly related to piracy.
Score: 52 Votes (Like | Disagree)
8692574 Avatar
126 months ago
Cant really blame Apple for data loss if you
(a) Don't make regular backups
(b) Install bit torrent clients (from a website no less) Which have little or no legitimate use other than piracy
to be expected when people use BitTorrent, I have zero sympathy for people who pirate stuff!
Torrent are used for more than piracy my friend, we are not in the early 2000 anymore!!

All Linux distribution are downoadable with torrent and they are 100% legit!
Score: 32 Votes (Like | Disagree)
elcdbot Avatar
126 months ago
Lol, I don't think I've met an even SLIGHTLY savvy computer user (Mac or PC) in the last eight years or so that uses a client other than uTorrent.
Given that ALL torrent apps are free, why would anyone download this????????
Stability and no ads. Never had a problem with Transmission as my default client.
Score: 27 Votes (Like | Disagree)
mnsportsgeek Avatar
126 months ago
Apparently it only affects users who downloaded it off of the website and not those who used the in app update.
Score: 27 Votes (Like | Disagree)
TheHorrorNerd Avatar
126 months ago
... if you use time machine
Cant really blame Apple for data loss if you
(a) Don't make regular backups
(b) Install bit torrent clients (from a website no less) Which have little or no legitimate use other than piracy
Score: 26 Votes (Like | Disagree)
Weaselboy Avatar
126 months ago
Looks like Apple has updated XProtect for this KeRanger malware already. This is from my xprotect.plist file.



Attachment Image
Score: 24 Votes (Like | Disagree)