Smartphone exploits are coming, as cybercriminals start to figure out how to make money by hacking mobile devices, two mobile security experts said Tuesday.
While mobile malware is still in its infancy, security vendors have seen a huge uptick in mobile attacks since late last year, said Tim Armstrong, a malware analyst at Kaspersky Lab, a Moscow-based cybersecurity vendor. Kaspersky Lab identified more than 1,550 mobile malware signatures in September, he said.
While many people have been predicting mobile malware for a while, "this might actually, finally, be the year," Armstrong said during a meeting of the Messaging Anti-Abuse Working Group in Arlington, Virginia. "It's only a matter of time before we see some really huge malware infections."
Right now, Nokia's Symbian operating system, popular outside the US, is the major target for mobile exploits, but Apple's iPhone and Android phones are likely to be growing targets, added Jarno Niemela, a senior researcher with F-Secure, a Helsinki-based security vendor.
In many cases, early attempts at smartphone exploits have lacked complexity, Niemela said. But both Niemela and Armstrong predicted that smartphone exploits will become more sophisticated and more common.
"These guys still are amateurs," Niemela said. "That's going to change when some of them strike gold."
Niemela and Armstrong provided several examples of already-attempted exploits during a talk on mobile malware.
One ploy targeted the Android platform with a fake movie player, with one version of the player billed as a pornography movie player. When Android users downloaded the app, which was available from a website not affiliated with Google's Android Marketplace, the fake media player installed an SMS (Short Message Service) exploit that sent out premium-priced SMSes, costing about US$5 each, without the phone owner's knowledge.
That scam was limited to Russian Android users, but it set an important precedent, Armstrong said. The criminals targeted small transactions, expecting that mobile-phone users, or more likely the employers paying the mobile-phone bills, wouldn't notice, he said.
"The cheapness of [the scam] was kind of an important factor in making it work," he added.
The way SMS works limits criminals to targeting people in their own country, but a potential growing area in mobile-phone malware is a premium international calling scam, Niemela said. The exploit works the same as the SMS scam , a user downloads an infected app but instead of sending premium SMSes, the compromised phone makes international long-distance calls, often once a month in the middle of the night, he said.
The per-minute charges for those calls can be several dollars, with the malware writer and a company that owns international premium rate numbers sharing in the profits. Again, with the malware making a limited number of calls each month, the company paying its employees' mobile-phone bills might not notice, he said.
"How many people here see their bill?" Niemela asked. In an audience of more than 100 people, no one raised a hand.
Other exploits for smartphones include fake applications that trick people into paying for them, and offers that include monthly charges in the fine print, similar to other online scams, Niemela said.
Some fake applications have been focused on banking apps, Niemela said. "That's scary," he added. "Those could have just as easily been banking Trojans."
Security researchers have also noticed scams where criminals are combining the Zeus Trojan, which typically steals personal information from PCs, with a mobile component, he said. In one case, criminals targeted customers of a bank in Spain.
The Zeus Trojan inserted a field on the bank's website asking for the user's SMS information and phone number. The criminals then sent a message to the customer's mobile phone, saying that their mobile-phone operating system needed to be updated. When customers downloaded the update, a Trojan was installed on their phone.