Software security company ESET reports that hackers have successfully ported older Linux-targeting malware to Mac OS X. OSX/Tsnunami.A is a new variant of Linux/Tsunami, a malicious piece of software that commandeers your computer and uses its network connection to attack other websites.
Like its Linux-based predecessors, Tsunami works by communicating via Internet Relay Chat, or IRC. The malware listens to a hardcoded list of IRC channels on specific servers, and responds to specific commands entered by others in those chatrooms. When triggered, infected computers can be instructed to attack individual websites, by sending large numbers of simultaneous requests. This is known as a Distributed Denial of Service attack (or a live Apple event); the huge number of simultaneous requests to a single website can cause it to crash or go offline.
Even worse, ESET says that Tsunami can force your computer to download additional malware or other software. The company also says that its antivirus software, ESET Cybersecurity for Mac, can detect and remove the malware.
Sophos says that the malware is distributed via a Trojan horse—malicious software that masquerades as something more innocent. Stay safe by ensuring that you only install software from trusted sources.