SecureMac has discovered a new trojan horse in the wild that affects Mac OS X, including Snow Leopard (OS X 10.6), the latest version of OS X. The trojan horse, trojan.osx.boonana.a, is spreading through social networking sites, including Facebook, disguised as a video. The trojan is currently appearing as a link in messages on social networking sites with the subject "Is this you in this video?"
When a user clicks the infected link, the trojan initially runs as a Java applet, which downloads other files to the computer, including an installer, which launches automatically. When run, the installer modifies system files to bypass the need for passwords, allowing outside access to all files on the system. Additionally, the trojan sets itself to run invisibly in the background at startup, and periodically checks in with command and control servers to report information on the infected system. While running, the trojan horse hijacks user accounts to spread itself further via spam messages. Users have reported the trojan is spreading through e-mail as well as social media sites.
It was just a matter of time, due to the popularity of Macs in recent years, before we'd see more malware targeting these systems. How prolific and common these types of attacks become only time will tell. It is interesting to me that attackers have determined its worth their effort to create, as the Java component of this Trojan is, cross platform code that can infect both Windows and OS X users.
Intego, a competitor to SecureMac, issued an advisory that deemed this worm to be of low risk:
Malware: OSX/Koobface.A Risk: Low Description: Intego has discovered a Mac version of the Koobface worm, which spreads via social networks such as Facebook, MySpace and Twitter. Intego's Virus Monitoring Center has been examining this malware for some time, and given the low level of risk, has not publicly issued information about it. Since other reports have been made public about this malware, Intego has decided to publish this security memo.
Reports have circulated discussing a Trojan horse, but without understanding either the scope or the functioning of this malware. This threat is a Mac OS X version of the Koobface worm, which is served as part of a multi-platform attack via a malicious Java applet. The malware itself is made up of a number of elements, though in order to simplify, we will use the term "Trojan horse" to describe it. (Technically, it propagates as a worm, is installed via a Trojan Horse, and installs a rootkit, backdoor, command and control, and other elements.)
Whether a real threat to many, or not, it's always good sense to be careful where one clicks.
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