Silicon Labs SiWx91x Devices SHA2/224 Hash Length Vulnerability Leading to Denial-of-Service

A vulnerability in SiWx91x devices causes the SHA2/224 algorithm to produce a 256-bit hash instead of the correct 224-bit length. This discrepancy triggers a software assertion, resulting in a Denial-of-Service (DoS) condition. Devices with an implemented watchdog will restart after the watchdog expires, while those without will require a hard reset for recovery.

Impact

Exploitation of this vulnerability leads to a Denial-of-Service condition, causing the device to become unresponsive until manually reset, except in cases where a watchdog timer is implemented, which allows for automatic recovery.