Defense Dept. bans Outlook, HTML email

Network security increased to "Infocon 4," meaning there is an increased risk of attack. HTML email and Outlook Web Access are seen as especially susceptible to attack.

The Defense Department has banned the use of Outlook Web Access email and is blocking all HTML email, as it raises network security conditions from the normal Information Condition (Infocon) 5 to Infocon 4, indicating heightened vigilance in preparation for operations or exercises or increased monitoring of networks due to increased risk of attack, Federal Computer Week reports.

A Navy user reported to the federal government IT publication that HTML messages were being automatically converted to plain text and a spokesman for Joint Task Force for Global Network Operations confirmed that the security level had changed.

The JTF-GNO spokesman declined to say why the command raised the threat level except to say that Infocon levels are adjusted to reflect worldwide social and political events and activities. He said the current threat level does not bar the use of attachments, including Power Point slides used for briefings.

Under Infocon 4, according to a Colorado National Guard newsletter, personnel are told that email from any unknown source, including unrecognized DoD accounts, should be viewed as harmful. There is a heightened alert for phishing emails as well.

The publication found on the Internet an internal message from Robins AFB, Ga., which concedes the ban "will significantly impact the way we presently conduct business,” since Outlook Web-based mail is how some 4,500 employees check mail. The base has come up with a workaround.