A vulnerability has been identified in Capital Embedded AR Classic 431-422 (All versions), Capital Embedded AR Classic R20-11 (All versions < V2303). The DHCP client application does not validate the length of the Domain Name Server IP option(s) (0x06) when processing DHCP ACK packets. This may lead to Denial-of-Service conditions. (FSMD-2021-0011)
https://www.tenable.com/cyber-exposure/2021-threat-landscape-retrospective
https://www.tenable.com/blog/nucleus13-13-vulnerabilities-found-in-siemens-nucleus-tcpip-stack
https://cert-portal.siemens.com/productcert/pdf/ssa-620288.pdf
https://cert-portal.siemens.com/productcert/pdf/ssa-114589.pdf
https://cert-portal.siemens.com/productcert/pdf/ssa-044112.pdf
https://cert-portal.siemens.com/productcert/html/ssa-620288.html
https://cert-portal.siemens.com/productcert/html/ssa-114589.html
https://cert-portal.siemens.com/productcert/html/ssa-044112.html