According to security researchers, if you receive a single square character via SMS starting today. Turn off your iPhone ASAP.

Cybersecurity researchers Collin Mulliner and Charlie Miller plans to demo the security flaw in the iPhone at today's Black Hat cybersecurity conference in Las Vegas. The flaw in the way the iPhone handles SMS allows a devious hacker the ability to send a quick SMS burst and remotely control your iPhone.

While being on the lookout for a square character is helpful, Miller contends that an attacker could adjust the SMS burst to contain a different image, or no image at all.

Once in control of your device a hacker, or jerk, could make phone calls, visit Web sites, use the camera and microphone, and actually send another SMS burst making your iPhone into a mobile zombie.

Miller told Forbes, "This is serious. The only thing you can do to prevent it is turn off your phone... Someone could pretty quickly take over every iPhone in the world with this."

The dynamic duo told Forbes that they informed Apple about the vulnerability more than a month ago with no response.

UPDATE: Before you start shutting off your iPhone and hiding under the blankets, remember that someone still needs your phone number in order to launch this attack. Hopefully we can test this out today to see the real vulnerability of your precious iPhone. 

Source: Forbes