A vulnerability, found in EdgeRouters Version 2.0.9-hotfix.5 and earlier and UniFi Security Gateways (USG) Version 4.4.56 and earlier with their DHCPv6 prefix delegation set to dhcpv6-stateless or dhcpv6-stateful, allows a malicious actor directly connected to the WAN interface of an affected device to create a remote code execution vulnerability.