Malware-infected ads now greatest threat to mobile security

Compromised or malicious adverts are now the main source of mobile malware, according to security firm Blue Coat.

Researchers from Blue Coat Security Labs found fake anti-virus scams are becoming increasingly prolific on smartphones and tablets, to the extent they are now the main source of infection.

These use social engineering techniques to persuade a user their device is already infected with malware, prompting them to change their security settings in order to cure' it, only for the real embedded malware to use this opportunity to infect.

"The threat relies on the user's own gullibility to follow fairly complex instructions and make changes to the security profile of their mobile devices that are detrimental to their device," the researchers said, in their annual mobile malware report.

The team claimed the increasing number of ads served to mobile users, which now outstrips the number for PCs and laptops, increases the likelihood of malware infection.

"The increased frequency of mobile ads conditions users to see them as normal, which makes users more vulnerable to the attacks that are launched through ads," they said.

The report advises people to avoid clicking on ads while using their mobile devices.

Blue Coat said Android devices were the most commonly targeted a finding backed up by Kaspersky Lab's most recent mobile malware report, published six days before Blue Coat's.

Kaspersky also noted the exponential increase in mobile malware, however its research found the majority of malware was delivered not through advertising but banking apps and websites.

"At the beginning of the year we knew only 67 banking Trojans, but by the end of the year there were already 1,321 unique samples," said Kaspersky's researchers, adding they expect to see this type of malware continue to grow over the course of 2014.