7 New Bugs in Bluetooth Let Hackers Impersonate As Legitimate Device & Launch DDoS Attacks

Bluetooth is currently used in millions of devices, and the Carnegie Mellon CERT Coordination Center (CERT/CC) has recently reported 7 security flaws in Bluetooth that allow attackers to impersonate as legitimate devices and launch DDoS attacks.

In total seven vulnerabilities were revealed, including the vulnerabilities affected during device pairing and provisioning to join a mesh network.

Researchers at the French National Agency for the Security of Information Systems (ANSSI) discovered and reported to the Bluetooth Special Interest Group (Bluetooth SIG), it’s a group that supervises the development of Bluetooth standards.

The security experts have pointed out these two specifications as vulnerabilities, and here they are mentioned below:-

Core Specification 5.2
Mesh Profile 1.0.1

However, just after the discovery, the Bluetooth Special Interest Group (Bluetooth SIG) has already provided the recommendations for each vulnerability, that are affecting the Core Specification 5.2, and Mesh Profile 1.0.1.

VU#799380: Devices supporting Bluetooth Core and Mesh Specifications are vulnerable to impersonation attacks and AuthValue disclosure https://t.co/qKx4Of6L9V
— CISA Cyber (@CISACyber) May 24, 2021

List of vulnerabilities

CVE ID: CVE-2020-26559
Vulnerability: Bluetooth Mesh Profile AuthValue leak
Affected specs: Mesh Profile Spec, v1.0 to v1.0.1
Notice: SIG Security Notice (https://www.bluetooth.com/learn-about-bluetooth/key-attributes/bluetooth-security/authvalue-leak/)

CVE ID: CVE-2020-26556
Vulnerability: Malleable commitment in Bluetooth Mesh Profile provisioning
Affected specs: Mesh Profile Spec, v1.0 to v1.0.1
Notice: SIG Security Notice (https://www.bluetooth.com/learn-about-bluetooth/key-attributes/bluetooth-security/malleable/)

CVE ID: CVE-2020-26557
Vulnerability: Predictable Authvalue in Bluetooth Mesh Profile provisioning leads to MITM
Affected specs: Mesh Profile Spec, v1.0 to v1.0.1
Notice: SIG Security Notice (https://www.bluetooth.com/learn-about-bluetooth/key-attributes/bluetooth-security/predicatable-authvalue/)

CVE ID: CVE-2020-26560
Vulnerability: Impersonation attack in Bluetooth Mesh Profile provisioning
Affected specs: Mesh Profile Spec, v1.0 to v1.0.1
Notice: SIG Security Notice (https://www.bluetooth.com/learn-about-bluetooth/key-attributes/bluetooth-security/impersonation-mesh/)

CVE ID: CVE-2020-26555
Vulnerability: Impersonation in the BR/EDR pin-pairing protocol
Affected specs: Core Spec, v1.0B to 5.2
Notice: SIG Security Notice (https://www.bluetooth.com/learn-about-bluetooth/key-attributes/bluetooth-security/impersonation-pin-pairing/)

CVE ID: N/A
Vulnerability: Authentication of the Bluetooth LE legacy-pairing protocol
Affected specs: Core Spec, v4.0 to 5.2
Notice: SIG Security Notice (https://www.bluetooth.com/learn-about-bluetooth/key-attributes/bluetooth-security/legacy-pairing/)

CVE ID: CVE-2020-26558
Vulnerability: Impersonation in the Passkey entry protocol
Affected specs: Core Spec, v2.1 to 5.2
Notice: SIG Security Notice (https://www.bluetooth.com/learn-about-bluetooth/key-attributes/bluetooth-security/passkey-entry/)

The devices that support the core technology of “Bluetooth” are vulnerable to the passkey input protocol that is used in Secure Simple Pairing (SSP), Secure Connections (SC), and LE Secure Connections (LESC).

In these circumstances, if a man-in-the-middle attack is received, then an attacker can easily spoof the device.

Moreover, the cybersecurity experts have asserted that in the Bluetooth Core Specification versions 4.0 – 5.2 the vulnerabilities are correlated with LE Legacy Pairing authentication.

So, here, if the attacker doesn’t know the temporary key, then it will be possible for the attacker to succeed in Phase 2 of legacy authentication by exploiting the confirmation items and random numbers of the other device in LE legacy pairing.

Affected vendors

Till now the Carnegie Mellon CERT Coordination Center (CERT/CC) has identified the following vendors who are affected:-

Red Hat
Cisco
Android Open Source Project (AOSP)
Cradlepoint
Intel
Microchip Technology

Among all these affected vendors, AOSP and Cisco is the first to respond and already working to distribute the security updates to fix the following flaws:-

CVE-2020-26555
CVE-2020-26558

While CERT/CC noted that the other affected vendors like Intel, Red Hat, and Cradlepoint have not yet issued any statements on this matter.