There were 350,000 different variants of unsolicited spam SMS messages accounted for globally in 2012, with 53,000 variants being logged for December alone.
This number denotes the different types of messages, not the frequency of messages received by all mobile users over the year, which would be considerably more.
The report by Cloudmark states that the most common spam message claims to offer gift cards (44%), while others include iPhone and iPad giveaways (11%) and Payment Protection Insurance (PPI) compensations (3%) which is particularly popular in the UK. However, the type of messages frequently changes in order to evade detection. Spam messages which offered free products were most likely to trick mobile users, as this type of spam totalled more than 50% of all messages.
Giveaway SMS messages often require additional details from the user in order to receive the “free gift”. The details are then used to continue to scam individuals.
The statistics have come from the GSMA Spam Reporting Service which launched at Mobile World Congress (MWC) last year in 2012. The service encourages mobile users to report their spam messages by forwarding the offending SMS to ‘7726’.
What should you do if you receive a spam message?
- Forward the message the short code "7726" (S-P-A-M)
- Messages will then be collated by the Spam Reporting Service and analysed to provide information to operators in the fight against spam messaging
The service was powered by Cloudmark which collates the data in order to tackle the issue of spam on behalf of carriers. The company provides carriers with information on spam content, senders and reporters which can lead operators to block numbers in attempt to reduce spam.
At the end of last year, Google's mobile operating system (OS), Android, was targeted by infected malware known as SpamSoldier. This Android botnet was seeded via SMS messages offering free versions of popular games which turned out to be pirated. However when the user ran the game, the program sent SMS spam, deleted itself and installed the pirated game.
In the two months the malware was active, Cloudmark estimated that the spammer sent between five and 10 million SMS messages, resulting in several thousand mobile devices being infected with the malware.
“As opposed to email, we often automatically trust that our SMS must come from someone we know or have done business with and attackers are well aware of this wide acceptance, using it to their advantage,” said Neil Cook, CTO at Cloudmark.