Spectra: New Wireless Escalation Targets
Jiska Classen and Francesco Gringoli disclose 'Spectra', breaking hardware coexistence isolation in Broadcom and Cypress Wi-Fi/Bluetooth combo chips.
Summary
Wireless Coexistence in Modern Mobile Silicon
To conserve board space and share 2.4 GHz antennas, smartphones and laptops combine Wi-Fi and Bluetooth into single combo chips with shared RAM and internal buses.
Deconstructing Broadcom and Cypress Coexistence Architectures
Jiska Classen and Francesco Gringoli analyze on-chip coexistence protocols, reverse engineering proprietary arbitration logic and shared hardware memory structures.
Lateral Movement Across Wireless Cores
Exploiting coexistence vulnerabilities allows an attacker who compromises the Wi-Fi core over the air to jump directly into the Bluetooth core, establishing stealthy persistence.
Extracting Keystrokes and Hardening Firmware
The researchers demonstrate over-the-air Bluetooth keystroke injection and coordinate security mitigations with silicon manufacturers.
Related talks
Main Stage·30 min
Jiska Classen · Francesco Gringoli
Jiska Classen and Francesco Gringoli discuss wireless combo chip architecture, coexistence cross-core attacks, and firmware mitigations.
The Linux Foundation·21 min
Li Xiaoming
Details set Up An Automated WiFi and Bluetooth Testing System for AGL and evaluates key implications for security practitioners.
Recon Conference·56 min
Security researchers examine technical aspects of Recon 2019 - Reversing and Exploiting Broadcom Bluetooth by Jiska & Dennis Mantz.


