A customer tries the Samsung Galaxy Note smartphone at a store in Seoul August 26, 2012. REUTERS/Lee Jae-Won

Google's Android operating system accounted for the vast majority of malware, or malicious software, infections on smartphones, a computer security firm said in a new report.

In its Mobile Threat Report for the fourth quarter of 2012, Helsinki-based F-Secure identified 96 new "families and variants" of threats targeting Android, which is nearly double the number recorded in the previous quarter.

As Android's share of the smartphone market rose last year -- now up to 68.8% -- so has its share of threats, which was 79%, F-Secure said.

That's in sharp contrast to the other major operating systems -- Blackberry, iOS (Apple) and Windows Mobile - which "may see some threats popping up once in a while."

The only other platform with a significant number of malware attacks was Symbian, the system discontinued by Nokia.

Android is "open source" software, meaning it can be modified by anyone.

Android says on its website says the platform is now on 400 million devices (smartphones and tablet computers) worldwide.