Special Edition is the blog for security testing business SE Labs. It explains how we test security products, reports on the internet threats we find and provides security tips for businesses, other organisations and home users.

Tuesday, 7 March 2017

Can You Hear Me?

Are cyber-scammers creating their own fake news stories to exploit? Jon Thompson investigates.

The UK media recently exploded with news of a new phone-based scam. Apparently, all that's needed for fraudsters to drain your bank account is a recording of you saying "yes". It runs as follows:
  1. Someone calls and asks if you can hear them
  2. They record you saying "Yes"
  3. They take your ID and money
What doesn't ring true is the lack of detail between steps 2 and 3. How, exactly, do attackers use this snippet of audio without the rest of your identity? Myth busting site Snopes has the answer: they don't. A good half hour of searching also failed to turn up a single verified victim of the scam despite a huge number of almost identical news reports warning people about it.

Whether it's a hoax or not, it's certainly easy to see how cyber-scammers can take advantage of the generated fear. Your "bank" calls, says you've been the victim of this very scam, and asks you to visit a special web site to enter your details and get your money back. Previous cybersecurity incidents certainly provide good evidence that such secondary scams may soon plague a phone near you.

Remember the TalkTalk hack of October 2015 and the scandalised headlines that followed? Four million customers were suddenly at risk, according to some ill-informed reports. The supposed Russian jihadist gang behind the attack was ransoming the purloined data. The Daily Express even reported that they were already raiding the accounts to fund their evil deeds.

The truth was far more mundane. A 17-year-old boy from Norwich had discovered an SQL injection using a vulnerability scanner, and syphoned off about 157,000 account records. However, with this data potentially in the wild, any attempted fraud experienced by TalkTalk customers was suddenly blamed on the hack.

In fact, telephone-based cyber-fraud is a numbers game. The more calls you make, the more likely it is that you'll hit the right set of circumstances. It's a brute force attack, and that's exactly what the scammers started to do. Nearly 18 months later, they're still finding ways to use the hack as a pretext to call unsuspecting customers.


At the time, some customers even reported that their broadband was being deliberately slowed by criminals, who then called them offering to fix the problem in exchange for visiting a phishing site and entering account details to get a special refund. Again, this is a numbers game: for every set of circumstances that make the scam work, there might be thousands of calls to people with the wrong broadband provider or who have no bandwidth problems. It's never the precision spear phishing attack it's reported to be by the bemused victims.

So, high profile hacks can subsequently spawn profitable campaigns for fraudulent callers keen to cash in on the chaos and fear. The problem is, juicy high profile hacks come along at random. What's needed is something more dependable.

This brings us back to the supposed "Can you hear me?" scam. Several reports in the past few days on Who Called and other very active nuisance call sites have mentioned the scam in passing as something else to look out for, but none say that this was the focus of the call being reported. The story has begun to take on a life of its own, but without any direct evidence that the scam actually exists.

Could it be that scammers themselves have concocted and spread a fake news story, which they intend to subsequently exploit with a campaign? It's not that great a leap of imagination, given the innovations developing in other areas of bulk cybercrime, such as ransomware. Only time will tell, but the next few months should be fascinating for both threat watchers and cyber-criminals alike.



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