Bluetooth Is Not Getting Safer

Over a year ago I published Seven Rules for Bluetooth at Starbucks. Recently, Armis, a security firm specializing in the Internet of Things (IoT), announced a new set of Bluetooth vulnerabilities they call BlueBorne. If you read “Seven Rules”, you have a good idea of what BlueBorne is like: hackers can get to your devices through Bluetooth. They can get to you without your knowledge. Windows, Android, Apple, and Linux Bluetooth installations are all vulnerable. Most of the flaws have been patched, but new ones are almost certain to be discovered.

Some of the flaws documented in BlueBorne are nasty: your device can be taken over silently from other compromised devices. Using BlueBorne vulnerabilities, hackers do not have to connect directly to your system. Someone walks within Bluetooth range with a hacked smartphone and you are silently infected. Ugly. Corporate IT should be shaking in their boots, and ordinary users have good reason to be afraid.

What should I do?

A few simple things make you much safer.

  • Be aware of your surroundings. Bluetooth normally has a range of 30 feet. More with special equipment, but whenever you don’t know who might be snooping within a 30-foot radius sphere, you are vulnerable. That’s half way to a major league pitcher’s mound and roughly three floors above and below.
  • Keep your systems patched. The problems Armis has documented in BlueBorne have been patched. Don’t give the bad guys a free ticket by leaving known soft spots unprotected. Make them discover their own holes. By patching regularly and quickly, you cut out the stupid and uninformed hackers. Smart hackers are rare.
  • Turn Bluetooth off when you are not using it or you enter a danger zone. When Bluetooth is turned off, you are safe from Bluetooth attacks, although you may still be affected by malware placed on your device while Bluetooth was turned on.

The seven rules for Bluetooth I published a year ago are still valid. Follow them.

Seven basic rules for Bluetooth

  1. Avoid high-stakes private activities, like banking transactions, when using Bluetooth in public.
  2. If you are not using Bluetooth, turn it off!
  3. Assume your Bluetooth connection is insecure unless you are positive it is encrypted and secured.
  4. Be aware of your surroundings, especially when pairing. Assume that low security Bluetooth transmissions can be snooped and intercepted from 30 feet in any direction, further with directional antennas. Beware of public areas and multi-dwelling buildings.
  5. Delete pairings you are not using. They are attack opportunities.
  6. Turn discoverability off when you are not intentionally pairing.
  7. If Internet traffic passes through a Bluetooth connection, your firewall may not monitor it. Check your firewall settings.

Checklist to Avoid the Next Cayla Doll

The Cayla doll story is frightening. The unintended consequences of a clever child’s toy amount to an invasion of  child privacy. I expect more such stories. Devices now in homes don’t just offer entertainment and convenience. They can also open doors to corporate and criminal intrusion. TV’s, refrigerators, along with our phones and laptops can all have cameras and microphones. Without your permission, someone could control these from outside your home.

Threat assessment

Security professionals follow a procedure called “threat assessment” to spot potential dangers. Threat assessment is a series of questions. Their answers yield a clear picture of threats. The questions are common sense, but you may not always think to ask them.

I recommend that before you install any device in your home or business, especially those connected to the internet, you go through a threat assessment. You may already do so without realizing it. Think through each of the five questions below. These questions apply to almost all computer security. The next five apply to non-computer devices connected to the network.

The basic checklist

  • What am I protecting? Most often, it is privacy of your family or business. Cayla can listen to you and your child and transmit what it hears to an unknown intruder or a cloud data business. The business or an intruder can speak to your child without your knowledge. Your television may record and analyze the conversations in your living room. Other devices may have similar abilities. Most often, you are protecting yourself from outside interference in your life.
  • Where does the threat come from? The source could be a business putting together a portfolio on you that they will use to sell things to you. Less likely, but still possible, the source may be a sinister criminal planning some kind of assault. A government agency, for good or bad, could use the device to collect information on you.
  • How likely is the threat? You probably know that data organizations collect data on you. And you have noticed that they have guessed whether you prefer heavy equipment parts or needlework supplies. On the other hand, the FBI probably hasn’t picked your refrigerator to monitor.
  • How great is the danger? Ads targeted to your online search profile may annoy you, but the danger to your person is slight. But a criminal stalker monitoring your phone conversations through your Bluetooth headset may be dangerous.
  • What are you willing to sacrifice for protection? Threats can be stopped, but is the effort is worth the benefit? All direct cyberthreats can be stopped or severely curtailed by going cash only and abstaining from the use of all electronic devices. Does the threat justify the sacrifice?

The Internet of Things

The threats here are from the Internet of Things (IoT), devices connected to the network but not usually called computers. The IoT is uniquely dangerous in two ways. First, IoT devices sneak in on us. We see them, but don’t think of them as computers connected to the internet. Even though many people have an idea of the threats involved in network computing, the IoT slips beneath their radar. Second, the designers of IoT devices often have no concept of good security practices and the devices are often shockingly vulnerable.

Questions for IoT security

  1. Find out how it connects to the network. Hard wiring, Wi-Fi, Bluetooth, and cellular are the main ways.
  2. Can you unplug it from the network? How easily? The first step when you suspect some kind of intrusion is to disconnect from the network. Make sure you can. Many IoT devices can’t be switched off like a laptop or desktop. If hackers remotely unlock your front door, you must stop them immediately. Don’t put yourself in a position where you must call a locksmith to install a new lock to keep your door closed.
  3. Are logs kept of who tinkers with the device? When the tinkering happened? The location of the tinkerer?
  4. Does the device collect data? If so, what is it and who has access to it? Can you control what is collected and who has access?
  5. Can the device firmware be updated with security fixes? Can it be done automatically?

These questions may not be easy to find answers for. Marketing literature is often sketchy or even deceptive on security. Engineering documents are better, but hard or impossible to get. However, even partial answers help evaluate the threat and underpin informed choices.