Linksys E5600 Risky Cryptographic Algorithm Vulnerability in Firmware Update Process

A vulnerability exists in the Linksys E5600 router running firmware version 1.1.0.26. The issue arises in the function verify_gemtek_header within the checkFw.sh file, part of the Firmware Handler component. The vulnerability is due to improper integrity verification using CRC (cyclic redundancy check), which can be easily bypassed. Attackers could craft malicious firmware that matches the CRC value of legitimate updates, allowing the harmful firmware to be installed on the device. This could lead to arbitrary code execution or a denial-of-service condition.

Impact

Exploitation of this vulnerability could result in arbitrary code execution on the affected device or cause a denial-of-service condition.