Did you know – enabling Bluetooth in non-discovery mode doesn't prevent access to your smartphone

Some smartphone users like to have Bluetooth turned on, but keep their devices in non-discoverable mode so other connected gadgets won't detect them. It turns out this precaution is just a myth, and keeping your device non-discoverable won't fully protect it against hackers bent on breaking into your phone. There are scanners and sniffer devices in existence that find your device's Bluetooth address and let infiltration commence even when it’s set to non-discoverable.

A significant vulnerability that eases the process is the "factory" default password used on the majority of Bluetooth devices, which is something to the tune of "0000" or "1234". Once someone has sniffed your Bluetooth address, chances are they can establish a connection using this PIN code. According to security researchers, it's this unreasonably simplified system that faciliates most cases of Bluetooth eavesdropping and so-called "Bluejacking"  – connecting to a phone and sending spam content. So one of the better things you can do in this regard is change your Bluetooth password to a less  PIN.

The way this goes is that most consumer devices rely on the Bluetooth Device Address (BD_ADDR) information as a security mechanism. Operating in discoverable mode, Bluetooth devices respond to page request messages issued by other gadgets with their BD_ADDR information. In non-discoverable mode, though, BD_ADDR information requests are ignored. It may be common sense, but devices in discoverable mode are especially vulnerable as they get easily identified with tools such as BTScanner that send repeated page request messages to all Bluetooth devices within range.

What's the take-away here? Keeping Bluetooth devices non-discoverable is still good practice, but it won't stop attackers. They are able to send con request messages to every common BD_ADDR prefix or OUI until the full BD_ADDR is known. Either that, or they can use a list of common BD_ADDR prefixes that lets an attacker test all known Bluetooth OUI values in less than 2 minutes. Ultimately, Bluetooth is best left switched off unless you're using it to pair a device or transmit information.

source: SANS Tech Institute via MakeUseOf




1. TechieXP1969

Posts: 14967; Member since: Sep 25, 2013

First off, if your BT is being connected too, most phones display that info on the screen. Since most people have their phone glued to their face, they should be able to see this and turn it off. Also unless someone is following you, there isnt much they can do over BT without you knowing it, especially since the range is very short. Unless you're using a signal booster, the range isnt even worth attempting to hack a moving target. The range is too short and most people are moving constantly. Unless you are important, no one is goign to hack your phone, no more than hacking your PC. Unless you are known to have alliances with a business where you have access to something worthwhile, people just dont go hacking every average joe on the street. These types of articles are always so stupid. if you are a CEO of a multi-billion dollar company or you work in banking, finance or similar; then "maybe" you should be more aware. You have a better chance of getting hit by a car, then having your phone hacked.

3. elitewolverine

Posts: 5192; Member since: Oct 28, 2013

No consumer is too small, it is this I am nothing mentality that creates a billion dollar industry. Also, go into a coffee shop, you are within range of 30 devices almost instantly. Now I don't know where you live, but it is not hard to visit the 'well' off places and bluejack into a few devices. Most people wont even know whats going on, they will dismiss the notification without a thought. They do so for everything from updates to messages.

4. epdm2be

Posts: 818; Member since: Apr 20, 2012

"dismiss" that BT-notification still doesn't grant you access. I think is all way too exaggerated.

5. hotmaillogin

Posts: 2; Member since: Feb 21, 2017

The article you have shared here very good. This is really interesting information for me. Thanks for sharing!

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