Denial of Service (DoS) in the Z-Wave S0 NonceGet protocol specification in Silicon Labs Z-Wave 500 series allows local attackers to block S0/S2 protected Z-Wave network via crafted S0 NonceGet Z-Wave packages, utilizing included but absent NodeIDs.

The Z-Wave specification requires that S2 security can be downgraded to S0 or other less secure protocols, allowing an attacker within radio range during pairing to downgrade and then exploit a different vulnerability (CVE-2013-20003) to intercept and spoof traffic.

Z-Wave devices from Sierra Designs (circa 2013) and Silicon Labs (using S0 security) may use a known, shared network key of all zeros, allowing an attacker within radio range to spoof Z-Wave traffic.