CVE-2019-11516 Explained : Impact and Mitigation
Learn about CVE-2019-11516, a vulnerability in the Cypress Wireless IoT codebase's Bluetooth component, allowing a heap-based buffer overflow. Find mitigation steps and affected systems.
The Cypress Wireless IoT codebase, previously owned by Broadcom, has a vulnerability in its Bluetooth component that can lead to a heap-based buffer overflow during device inquiry.
Understanding CVE-2019-11516
This CVE involves a specific vulnerability in the Bluetooth component of the Cypress Wireless IoT codebase.
What is CVE-2019-11516?
The vulnerability arises from improper handling of Extended Inquiry Responses (EIRs) in the Bluetooth component, allowing for a heap-based buffer overflow during device inquiry. This overflow can be exploited to overwrite existing functions with arbitrary code.
The Impact of CVE-2019-11516
The vulnerability can be exploited by an attacker connecting to the victim's device within a short timeframe using different source addresses, leading to a write-what-where vulnerability.
Technical Details of CVE-2019-11516
This section provides more detailed technical information about the CVE.
Vulnerability Description
The issue occurs due to the eir_handleRx() function not properly discarding Reserved for Future Use (RFU) bits, causing them to be included in the length of an EIR, leading to a heap-based buffer overflow.
Affected Systems and Versions
- Product: n/a
- Vendor: n/a
- Versions: n/a
Exploitation Mechanism
- Attacker needs to connect to the victim's device within a short timeframe using different source addresses
- Victim's Bluetooth stack allocates buffers with attacker-controlled data while resolving device names
- Heap corruption leads to the device name being written to a location controlled by the attacker
Mitigation and Prevention
Steps to address and prevent the CVE.
Immediate Steps to Take
- Apply patches or updates provided by the vendor
- Monitor Bluetooth connections for suspicious activity
Long-Term Security Practices
- Regularly update firmware and software
- Implement network segmentation to limit the impact of potential attacks
Patching and Updates
- Check for patches from Cypress or Broadcom to address the vulnerability