If you're thinking of plugging your smartphone into a public USB port to charge it up, be careful.
A number of cafes, airports, and public transport vehicles have USB hubs where you can juice up your phone, but sadly, they can be hacked, and that will leave your device vulnerable to attack.
The researchers over at Kaspersky Labs found that they could install a third-party app onto a phone via a USB cable, and of course, if they were criminals, that could easily be a virus.
During their tests, they discovered that they could grab a load of personal data while the devices were charging - this included both Apple and Android phones.
Some of the data they got their hands on included the device name, device manufacturer, device type, serial number and lists of files.
Of course, as well as USB connections being a risk, so too are public WiFi connections, which means you need to be vigilant when using them.
"The security risks here are obvious: if you're a regular user, you can be tracked through your device IDs; your phone could be silently packed with anything from adware to ransomware. And, if you're a decision-maker in a big company, you could easily become the target of professional hackers," said Alexey Komarov at Kaspersky Lab.
"And you don't even have to be highly-skilled in order to perform such attacks, all the information you need can easily be found on the Internet."
The problem is that phones automatically exchange information with whatever device they're connected to. A couple of years ago, The Hacking Team in Italy did exactly that.
Kaspersky Labs continued: "That would not have been as easy to achieve if smartphones did not automatically exchange data with a PC upon connecting to the USB port."
What To Do?
You should ensure that you only ever plug your phone into trusted computers, using safe USB cables. So basically, use the one you always use, and charge it through machines you've got at home, or somewhere where you can be sure there's little chance of anyone getting at it.
You can see the best Android anti-virus apps, here.
You should make sure your phone is secure, and install anti-virus software. They can detect malware, even when your smartphone is charging up.
Make sure you have the most recent mobile operating system, so the most recent bug-fixes and security updates are in place.