Missing Encryption of Security Keys vulnerability in Silicon Labs OpenThread SDK on 32 bit, ARM (SecureVault High modules) allows potential modification or extraction of network credentials stored in flash. This issue affects Silicon Labs OpenThread SDK: 2.3.1 and earlier.

TI’s BLE stack caches and reuses the LTK’s property for a bonded mobile. A LTK can be an unauthenticated-and-no-MITM-protection key created by Just Works or an authenticated-and-MITM-protection key created by Passkey Entry, Numeric Comparison or OOB. Assume that a victim mobile uses secure pairing to pair with a victim BLE device based on TI chips and generate an authenticated-and-MITM-protection LTK. If a fake mobile with the victim mobile’s MAC address uses Just Works and pairs with the victim device, the generated LTK still has the property of authenticated-and-MITM-protection. Therefore, the fake mobile can access attributes with the authenticated read/write permission.

OpenThread before 2019-12-13 has a stack-based buffer overflow in MeshCoP::Commissioner::GeneratePskc.