MCO 5239.2B — Marine Corps Cybersecurity

MCO 5239.2B governs Marine Corps cybersecurity policy, procedures, tasks, conditions, and standards implementation guidance for the MCEN.

Search MCO 5239.2B

  • Publication number: MCO 5239.2B
  • Title: MARINE CORPS CYBERSECURITY
  • Date: 5 Nov 2015
  • Proponent: 05000 General Admin & Management
  • Status: Current

View MCO 5239.2B on armypubs.army.mil


It delineates organizational actions for securing communications, digital information, systems, and networks, including precautions against cyber attacks. It establishes a comprehensive framework for security governance and controls over information resources and addresses protection of data in transit and at rest on the MCEN.

Topics covered

  • Marine Corps cybersecurity
  • MCEN security
  • Cyber attack precautions
  • Information resources security governance
  • Data in transit and at rest
  • Secure networking capability

Questions and answers

When will the Marine Corps SCI Networks cybersecurity annex be published?

An Annex providing the policy, procedures, and standards implementation guidance for Marine Corps SCI Networks will be published 180 days from the issuance of this Order. (paragraph 3)

What networks make up the MCEN?

The MCEN is both, the MCEN - NIPRNet (MCEN-N) and the MCEN SIPRNet (MCEN-S); however, this document will refer to both networks as one MCEN. (paragraph 3)

What does the Marine Corps cybersecurity program protect?

In accordance with references (c) and (d) the Marine Corps will employ a comprehensive cybersecurity program designed to protect and defend the MCEN and the data in transit and the data at rest on the MCEN to ultimately support the commander’s information needs. (paragraph 4)

What can result from failing to implement the cybersecurity measures in MCO 5239.2B?

Operationally, failure to implement the proactive or corrective cybersecurity measures identified in this Order may result in critical information loss, capture, corruption, or lack of timely access which may potentially lead to mission failure. (paragraph 1)

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