Malware is estimated to affect between 10,000 and 30,000 phones on any given day. Malware, mostly found on Chinese phones, works by using GingerBreak, a tool that gives users root access to Android 2.3 Gingerbread. Android.Bouncer has been used quietly for several months; in the second half of 2011, the Android market saw a 40 percent decrease in malware apps identified as potentially malicious, compared to the first half of the year. Google blocks them before they get into the official Android Market.
Source: https://thehackernews.com/2012/02/androidbmaster-exploits-root-access-to.html