Security firm discovers alarming number of Macs infected with malware

Apr 24, 2012 17:11 GMT  ·  By

Shocking discovery from security vendor Sophos today - according to the company headquartered in Boston, US and Oxford, UK., one in five Macintosh computers carries malware.

A press release issued by the security company today cites new research that has churned up a disturbingly high level of malware on Mac computers.

Both Windows and Mac threats have been discovered, which makes matters even worse for work environments that harbor both Macs and Windows PCs.

After analyzing a snapshot of 100,000 Mac computers running its free anti-virus software, Sophos discovered that “one in five machines was found to be carrying one or more instances of Windows malware.”

Sophos explains that “although Windows malware on Macs will not cause symptoms (unless users also run Windows on their computer), it can still be spread to other computers.”

The Mac is still far safer than Windows PCs, as only 2.7 percent (one in 36) of Macs were found to be carrying malware executable on Mac OS X.

"Some Mac users may be relieved that they are seven times more likely to have Windows viruses, spyware and Trojans on their Macs than Mac OS X-specific malware, but Mac malware is surprisingly commonly encountered," said Graham Cluley, senior technology consultant at Sophos. "Mac users need a wake-up call about the growing malware problem."

Cluley points out to the recent Flashback botnet, which infected more than 600,000 machines, as the dominant figure on the chart of Mac-based threats.

"Mac malware can spread via USB stick, email attachments, website download, or even a silent drive-by installation where the user doesn't realize their Mac's security has been subverted," continued Cluley.

"Cybercriminals view Macs as a soft target, because their owners don't typically run anti-virus software and are thought to have a higher level of disposable income than the typical Windows user. Mac users must protect their computers now or risk making the malware problem on Macs as big as the problem on PCs."

Some of the malware discovered on the 100,000 Mac computers dated back to 2007. These machines would have been easily cleansed, had users run an anti-virus products, said Sophos.

"The simple fact is that you can scan your Mac for infection from your armchair. The test is painless and free; you just download an anti-virus product and allow it to check your computer and protect it against infections in the future," explained Cluley.

Sophos encourages home users to download their free Anti-Virus for Mac.