Mobile malware has increased significantly, and Android users are two-and-a-half times as likely to encounter malware today than just six months ago, says Lookout.
Based on data collected from more than 700,000 apps and 10 million devices worldwide, the company estimates that between a half million and one million users were affected by mobile malware in the first half of 2011.
At the same time, web-based threats which operate across platforms, have emerged as a significant part of the threat landscape with three out of ten mobile users likely to click on an unsafe link, including malicious and phishing links, over the course of a year.
GGTracker, discovered in June 2011, is the first known Android malware that specifically targets U.S.-based Android users. This malware signs users up for premium text message subscription services without their knowledge, charging $10 per service to a person’s phone bill. In some cases users were charged for multiple services with total charges ranging up to $50.
Previously, these types of attacks mainly affected Android users in China, Russia and Eastern Europe. In addition to the monetary impact of the malware, GGTracker used new techniques to broadly distribute the malware including malvertising.
During the first half of 2011, the company found that attackers repackage legitimate applications with malware, creating Trojan applications that appear to be legitimate, but in fact are malicious, and post them to app stores and download sites. More recently, malware writers are using new techniques to secure wide distribution.
Attackers employ a tactic called malvertising, whereby they use mobile ads to direct users to a malicious website that triggers an automatic download of malware. Additionally, Lookout saw the first Update Attack, in which an attacker first publishes a legitimate application with no malware, and once they have a large user base, they release an update that includes malware so the entire user base gets the updated infected application.
During the first half of 2011, the number of unique apps with malware found on markets and download sites grew from 80 to 400 apps. Two of the most prevalent threats, DroidDream and GGTracker, were regularly published in new apps over the first half of the year. During this period, the authors of DroidDream released more than 80 unique applications with variations of malware to take control of a user’s phone. Similar to DroidDream, the authors of GGTracker continue to publish new infected apps across app stores and download sites, bringing its total infected app count up to 15 since mid-June.
Tips for staying safe:
- Only download apps from trusted sources, such as reputable app stores and download sites. Remember to look at the developer name, reviews, and star ratings.
- After clicking on a web link, pay close attention to the address to make sure it matches the website it claimed to be.
- Download a mobile security tool that scans every app you download for malware and spyware, and can help you locate a lost or stolen device. For extra protection, make sure your security app can also protect from unsafe websites.
- Be alert for unusual behavior on a phone. This behavior could be a sign that the phone is infected. These behaviors may include unusual text messages, strange charges to the phone bill, and suddenly decreased battery life.