Transmission has been one of the longtime favourite apps for sharing and downloading torrent files on Mac OS X and has been recently flagged for malware. Being open sourced software, the Transmission BitTorrent client version downloaded last Friday or Saturday are sketchy and are downloaders are being warned to update to the latest 2.92 version to avoid being targeted by a ransomware that infiltrated an earlier version of the open source software.
KeRanger is the is believed to be the "first fully functional" ransomware on the OS X platform. When incorporated into an app, the malware connects to a remote server via the Tor anonymizing service, then "begins encrypting certain types of document and data files on the system."
The malware then "demands that victims pay one bitcoin (about $400) to a specific address to retrieve their files." Researchers say the malicious code is "under active development" and seems to be trying to also encrypt users' Time Machine backups to also prevent them from being able to recover their backed up data.
Other options for Mac users wanting a stable BitTorrent apps include uTorrent, xTorrent and Acquisition.
Source: AppleInsider