Norfolk Southern Corporation is substantially complete with a root-cause analysis of the system outage that occurred on Monday. The company provided the following update on the findings to date:

We are substantially complete with a root-cause analysis of this outage. To date, we have found no indication that this was related to an unauthorized cybersecurity incident.

Norfolk Southern's data storage system is manufactured and maintained by a leading global technology provider. During a routine maintenance procedure being performed by our vendor, a defect in their software created an error which caused both our primary and recovery data storage systems to become unresponsive. This in turn affected our core operational systems. We are working closely with the vendor to understand the steps they are taking to strengthen their systems to prevent this incident from reoccurring and identify opportunities for Norfolk Southern to become more resilient.

Throughout this, our IT team worked tirelessly to restore our systems, our Marketing team worked closely with customers to keep them informed, and our Operations team safely brought our network back online. We are making progress on the temporary backlog of trains that resulted from this incident, and expect a full recovery of network fluidity in the coming weeks.