[Amnesia:33](https://www.forescout.com/company/resources/amnesia33-how-tcp-ip-stacks-breed-critical-vulnerabilities-in-iot-ot-and-it-devices/) is a group of 33 vulnerabilities in open-source TCP/IP stack libraries. The vulnerabilities may be present in a wide range of operational technology, IoT, and connected device implementations.

An issue was discovered in Contiki through 3.0 and Contiki-NG through 4.5. The code for parsing Type A domain name answers in ip64-dns64.c doesn't verify whether the address in the answer's length is sane. Therefore, when copying an address of an arbitrary length, a buffer overflow can occur. This bug can be exploited whenever NAT64 is enabled.