CVE-2019-19196 Explained : Impact and Mitigation

Telink Semiconductor's BLE SDK versions released before November 2019 have a vulnerability in their implementation of the Bluetooth Low Energy Secure Manager Protocol (SMP), allowing for a denial of service attack.

Understanding CVE-2019-19196

Telink Semiconductor's BLE SDK versions prior to November 2019 are susceptible to a buffer overflow vulnerability in the Bluetooth Low Energy Secure Manager Protocol (SMP), potentially leading to a denial of service.

What is CVE-2019-19196?

The vulnerability in Telink Semiconductor's BLE SDK versions allows an attacker within radio range to exploit a buffer overflow by sending specially crafted packets, resulting in a denial of service (crash) due to an accepted key size exceeding 16 bytes.

The Impact of CVE-2019-19196

This vulnerability could be exploited by an attacker within radio range, leading to a denial of service (DoS) attack on affected devices utilizing Telink Semiconductor's BLE SDK versions released before November 2019.

Technical Details of CVE-2019-19196

Telink Semiconductor's BLE SDK versions prior to November 2019 are affected by a critical vulnerability in the implementation of the Bluetooth Low Energy Secure Manager Protocol (SMP).

Vulnerability Description

The vulnerability allows an attacker within radio range to trigger a denial of service (DoS) attack by exploiting a buffer overflow in the SMP implementation.

Affected Systems and Versions

Telink Semiconductor BLE SDK versions released before November 2019
TLSR8x5x up to version 3.4.0
TLSR823x up to version 1.3.0
TLSR826x up to version 3.3

Exploitation Mechanism

Attacker within radio range sends specially crafted packets
Crafted packets exceed the accepted key size of 16 bytes
Buffer overflow occurs, leading to a denial of service (crash)

Mitigation and Prevention

It is crucial to take immediate steps to address and prevent the exploitation of CVE-2019-19196.

Immediate Steps to Take

Update affected Telink Semiconductor BLE SDK versions to patched releases
Implement network segmentation to limit exposure
Monitor network traffic for any signs of exploitation

Long-Term Security Practices

Regularly update software and firmware to the latest versions
Conduct security assessments and penetration testing on BLE implementations
Educate users and developers on secure coding practices

Patching and Updates

Telink Semiconductor has likely released patches for the affected BLE SDK versions
Ensure all devices using the vulnerable SDK are updated to the latest secure versions