CVE-2020-11901: Remote Code Execution Via Invalid DNS Response in Treck TCP/IP stack (Ripple20)

This vulnerability can be triggered by answering a single DNS request made from the device. It affects any device running Treck with DNS
support and can be used to perform Remote Code Execution on a Schneider Electric APC UPS. DNS requests may leave the network in
which the device is located, and a sophisticated attacker may be able to use this vulnerability to take over a device from outside the
network through DNS cache poisoning, or other methods. Thus an attacker can infiltrate the network and take over the device with one
vulnerability bypassing any security measures. The malformed packet is almost completely RFC compliant, and so it will likely be difficult
for security products such as firewalls to detect this vulnerability. On very old versions of the Treck stack, still running on some
devices, the transaction ID is not randomized making the attack easier.