CVE-2019-19195

The Bluetooth Low Energy implementation on Microchip Technology BluSDK Smart through 6.2 for ATSAMB11 devices does not properly restrict link-layer data length on reception, allowing attackers in radio range to cause a denial of service (crash) via a crafted packet.

Recent assessments:

pbarry-r7 at April 16, 2020 4:12pm UTC reported:

This vuln is part of a related batch named SweynTooth from researchers at the Singapore University of Technology and Design. The SweynTooth vulnerabilities lie within certain Bluetooth Low Energy (BLE) SDKs for Systems-on-a-Chip (SoC), which can make proliferating fixes to affected devices in the field a slow going.

Vulnerable devices need to be within BLE radio range in order for an attacker to target. A successful exploit will crash the target by sending a “too short” link layer PDU. That said, the watchdog mechanism (enabled by default in the SDK) will notice and reboot the device, making this a short-lived Denial of Service for devices which have the watchdog enabled. A detailed explanation can be found here in the original disclosure, as well as some potentially vulnerable devices in this list. It appears the SoC manufacturer is still working on fixes for their vulnerable SDK(s).

EDIT: Attacker Value for this item largely depends on the type of device the vulnerable target is and behavior the device exhibits when successfully exploited.

Assessed Attacker Value: 3
Assessed Attacker Value: 3Assessed Attacker Value: 4