Specially crafted PROFINET DCP broadcast packets could cause a denial of service condition of affected products on a local Ethernet segment (Layer 2). Human interaction is required to recover the systems. PROFIBUS interfaces are not affected.
https://www.siemens.com/cert/pool/cert/siemens_security_advisory_ssa-284673.pdf
https://ics-cert.us-cert.gov/advisories/ICSA-18-023-02
https://cert-portal.siemens.com/productcert/pdf/ssa-546832.pdf
https://cert-portal.siemens.com/productcert/pdf/ssa-293562.pdf
https://cert-portal.siemens.com/productcert/pdf/ssa-284673.pdf
https://cert-portal.siemens.com/productcert/html/ssa-546832.html
https://cert-portal.siemens.com/productcert/html/ssa-293562.html
https://cert-portal.siemens.com/productcert/html/ssa-284673.html