An authentication weakness exists in the TP-Link TDDP v2 service of TP-Link RE305 V3. TDDP v2 uses a fixed and derivable cryptographic key, which may allow an unauthenticated attacker on the same local network to forge protocol packets and access privileged TDDP operations, including functionality that can lead to operating-system command execution when the TDDP service is running and accessible. Successful exploitation may allow an unauthenticated attacker on the same local area network to execute arbitrary system commands with root privileges.