SpamSoldier engineered to hide traces of malicious activity.
Network security firm Cloudmark has issued a warning to Android handset users regarding a new spam-forwarding botnet.
Known as SpamSoldier, the malicious mobile application, which appears to be confined to the U.S., comes into affect should a user download counterfeit versions of Android games stored on a Hong Kong server as opposed to the central Google Play store.
The copied games are accessed through a text message that promises to deliver free versions of titles such as Need for Speed: Most Wanted and Angry Birds Star Wars.
"Download Grand Theft Auto 3 & Need for Speed Most Wanted for Android phones for free at http://[redacted].mobi for next 24hrs only!" the message reads.
Should the app be installed, users will notice that the icon disappears from the home screen. The app will then connect to a remote server in order to obtain a list of target numbers, after which it'll commence the sending of spam messages through the infected handset.
"You better have an unlimited message plan or your phone bill may come as a bit of a shock," Cloudmark stressed.
"Compared with PC botnets this was an unsophisticated attack. However, this sort of attack changes the economics of SMS spam, as the spammer no longer has to pay for the messages that are sent if he can use a botnet to cover his costs. Now that we know it can be done, we can expect to see more and more complex attacks that are harder to take down."
Mobile antivirus firm Lookout, a company that recently signed a deal with EE to provide free virus protection for Android next year, added that SpamSoldier is engineered in a way that allows it to become hidden and remove any trace of "malicious activity" by intercepting text replies and hiding outgoing messages.
It was recently revealed that Android's 4.2 malware scanner has a detection rate of 15 percent. The amount of malware itself affecting Google's platform surged during 2012's Q3.