NEW YORK (CBSNewYork) — Smartphone and tablet users beware: there has been a sharp increase in the number of criminal hack attacks on mobile devices.

And as CBS 2’s Don Dahler reported Tuesday, you may have no idea you are the victim of a viral vandalism attack.

A mobile phone that is running slowly or using an unexplained amount of airtime, or acting strangely in other ways, could be harboring a virus.

“My phone started singing a song and the song had a couple curse words in it and I, there’s no way I could make it stop,” said Leanne Karlgut.

Cyber criminals are infiltrating phones and tablets at an alarming rate. Reports of disruptive software, or malware, that can gather sensitive information have increased 600 percent in recent years.

Cyber security expert George Waller, of StrikeForce Technologies, estimated that nearly 50 percent of all smartphones and tablets are already infected.

“As more people are using the phone for both their personal use and their business use, the malware writers are viewing that as a good, a good spot to hit you,” Waller said.

And people often have no idea they have been hit. Your phone can be infected simply by clicking on a poisoned link or text.

Some viruses can record every text or e-mail you write, and every password you enter.

“It could get your banking credentials and essentially go into your bank, act as you,” Waller said.

And if you use a mobile wallet app, some experts worry when you tap and pay using your phone, criminals could intercept the short-wave radio chip transmission, sending your credit card information from the phone to a retailer you yourself never bought anything from.

There is also a way for crooks to use their own phones to steal your credit card information, using a smartphone to pick up signals directly from a credit card.

“So I have one person standing next to a victim, and my accomplice at a retail location could be halfway around the world, and they’ve just spent this person’s credit card,” said Eddie Lee of Blackwing Intelligence.

To stay ahead of cyber crooks, the Wireless Trade Association offers some recommendations to safeguard your phone.

• Download smartphone security software.
• Never click on suspicious links
• Buy apps only from well-known vendors

“The industry is working incredibly hard to try to protect both its networks and its own users,” said Jot Carpenter of CTIA-The Wireless Association.

Have you ever experienced a mobile hack attack? Please leave your comments below…