The Microsoft Malware Protection Center reported that it found a new Mac backdoor. However, it appears Intego and Kaspersky had already found it.
Microsoft researchers uncovered a new piece of Mac malware
that can install remote-control backdoors on compromised machines. Other
researchers questioned whether it was a credible threat at this time.
Microsoft researchers came across the backdoor, named Olyx,
in a package which contained a different Windows malware, according to a July
25 post on the Microsoft
Malware Protection Center blog
. This Mac backdoor appears to be very similar
to the Gh0st RAT malware that targeted older Windows systems back in 2009.
The package contained a Mac binary file that "installs
and runs in the background without root or administrator privileges," wrote
Meths Ferrer, a threat researcher for MMPC based in Melbourne, Australia.
Olyx pretends to be a Google application support file by
creating a Google folder in the Application Support directory. The backdoor
runs only once when the user logs in, so on systems with multiple user
accounts, it will execute once for every account. When launched, it opens a
remote connection with a South Korean IP address. With the connection in place,
a remote attacker can upload, download and navigate through files on the
compromised machine, according to Ferrer.
Mac security vendor Intego was dismissive of Microsoft's
discovery, noting that its researchers had "spotted this backdoor some
time ago" and updated its malware definitions for its VirusBarrier
antivirus software on June 30. Olyx also showed up in Kaspersky
Lab's June Monthly Malware Statistics
"There is little threat to this malware, as it is not
found in the wild in any form that can be installed on Macs," Intego said
on its Mac
A backdoor on its own is fairly harmless. It must either be
manually installed by a user who was tricked into running the file or be
bundled with other malware before it can infect the system. Olyx was not well-designed and can't be
easily installed on user machines to compromise them, so it's not a real
threat, Intego said.
"We don't publicize such malware by issuing security
alerts, because the threat is not serious enough," Intego said.
Olyx is very different from the MacDefender fake antivirus
scammed users in May. MacDefender used various social engineering tricks to
trick users into downloading the software and then handing over their credit
Despite the low threat, Intego proactively updated its
antivirus definitions so that if Olyx ever packaged into an "effective
payload" to infect users, VirusBarrier users will already be protected,
the company said.
Mac-based threats remain relatively obscure and even with
Mac Defender on the scene, Mac malware accounts for a minuscule fraction of
total malware. It's easy to get worked up about new and sophisticated attacks
as they are discovered, but not all of them become actual threats, said Tal
, a member of Imperva's Application Defense Center. As for reports of
researcher Charlie Miller
manipulating the micro-chips on a Mac laptop battery
last week, Be'ery said, "Cool? Yeah! Sophisticated? Absolutely! Practical?
"No matter how obscure and fun an attack sounds, we
need to focus on the real threats," Be'ery said.