A vulnerability has been identified in SCALANCE XM-400 Family (All versions < V6.4), SCALANCE XR-500 Family (All versions < V6.4). The OSPF protocol implementation in affected devices incorrectly handles the number of LSA fields in combination with other modified fields. An unauthenticated remote attacker could create a permanent denial-of-service condition by sending specially crafted OSPF packets. Successful exploitation requires OSPF to be enabled on an affected device.

References

• https://nvd.nist.gov/vuln/detail/CVE-2020-28393
• https://cert-portal.siemens.com/productcert/pdf/ssa-116379.pdf
• https://us-cert.cisa.gov/ics/advisories/icsa-21-131-10