Microsoft evaluates the security of its infrastructure on an ongoing basis and part of this evaluation includes working with our vendors, the open source community and internal test labs to identify and mitigate critical security issues. On March 2nd, Cisco released its bi-annual security bulletin which included advisories affecting equipment used by many Cloud Service Providers, including Microsoft. We are currently reviewing all the details of this bulletin and then deciding what, if any, actions need to be taken to remediate the risk.
If you need more details on the specific vulnerabilities disclosed, please see https://tools.cisco.com/security/center/publicationListing.x.
UPDATE: We have completed our evaluation and updated all impacted hardware.