Cybersecurity researchers found that hackers can now launch a type of brute-force attack called Key Negotiation of Bluetooth, or KNOB.
The main problem here is that all the Bluetooth chips manufactured by Intel, Broadcom, Apple, and Qualcomm are vulnerable to KNOB attacks.
KNOB cyberattacks are used to target and exploit a flaw present in the firmware of a device’s Bluetooth chip.
The Bluetooth vulnerability used in this type of attack is known as CVE-2019-9506.
This exploitation allows hackers to perform a Man in the Middle (MiTM) attack that could leak potentially user sensitive data.
A KNON cyber attack can happen under two circumstances of Bluetooth programming.
The attack begins when, Bluetooth allows the use of keys that have a minimum length of 1 byte, and because of this hackers can easily circumvent them with a brute-force attack.
Researchers recommend the implementation of a 1-byte lower limit to follow international encryption regulations and keep everyone safe.
Be aware! This KNOB cyber-attack endangers all standard-compliant Bluetooth devices, regardless of their Bluetooth version number and implementation details.
The second circumstance does not check changes in entropy, which occurs when two devices start to “negotiate” the key length they will be used to encrypt their connection. Meaning that this cyberattack is even worse than the previous. Because it happens in the pre-pairing phase which isn’t encrypted, so the device receiving the pairing request will have no choice but to accept the low-entropy key.
Remember everything can be hacked. In order to stay away from any threats related to the cyber world, we recommend the install an antivirus for Mac, like Antivirus CB from AppStore, on every device that you own.
The good news is that cybersecurity researchers have already disclosed the vulnerability to the Bluetooth Special Interest Group (SIG).
Shortly after SIG announced that it has remedied the vulnerability by updating the Bluetooth Core Specification to recommend the use of encryption keys with a minimum of 7 bytes of entropy for BR/EDR connections.
To know if your Bluetooth devices are vulnerable to the KNOB attack, recall if you have updated them since late 2018. If you haven’t, chances are that your devices are vulnerable.
This is how to protect yourself:
Patch all your Bluetooth devices.
If you own any devices that are maid by the following manufacturers you must update all the following operating systems to their latest version:
Apple: iOS, macOS, watchOS
Cisco: IP phones and Webex
Red Hat: All platforms
We would continue to monitor the cybersecurity world. Meanwhile, users should keep a keen eye out for any cyber-attacks. Remember to use antivirus for Mac like Antivirus CB which can be found on AppStore to try for free.