Due to an increased network threat condition, the Defense Department is
blocking all HTML-based e-mail messages and has banned the use of
Outlook Web Access e-mail applications, according to a spokesman for
the Joint Task Force for Global Network Operations.
An internal
message available on the Internet from the Defense Security Service
(DSS) states that JTF-GNO raised the network threat condition from
Information Condition 5, which indicates normal operating conditions,
to Infocon 4 “in the face of continuing and sophisticated threats”
against Defense Department networks.
Infocon 4 usually
indicates heightened vigilance in preparation for operations or
exercises or increased monitoring of networks due to increased risk of
attack.
The JTF-GNO mandated use of plain text e-mail because
HTML messages pose a threat to DOD because HTML text can be infected
with spyware and, in some cases, executable code that could enable
intruders to gain access to DOD networks, the JTF-GNO spokesman said.
In an e-mail to Federal Computer Week, a Navy user said that any HTML
messages sent to his account are automatically converted to plain text.
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.
He also declined to
tell FCW what other restrictions on e-mail that JTF-GNO has imposed.
But a December 2006 newsletter of the Colorado National Guard said that
under Infocon 4, Guard members receiving e-mails from any unknown
source, including “mail received from unrecognized Department of
Defense accounts,” should be viewed as potentially harmful.
The
Colorado Guard newsletter also alerted personnel to be vigilant against
e-mail “phishing” attempts to gain personal information.
The
ban on use of Outlook Web mail will hit thousands of users at Robins
Air Force Base, Ga., according to an internal message available on the
Internet. The ban on the use of Outlook Web Access “will significantly
impact the way we presently conduct business,” due to the fact that
that Web mail is the primary means of e-mail access for 4,500 employees
at the base, according to the message.
Robins has developed a
work-around for these users to access Outlook directly by logging on to
government computers with their common access cards, the internal
message said.
JTF-GNO raised the DOD network threat level to
Infocon 4 in mid-November after an attack on the networks at the Naval
War College (NWC) required NWC to take its systems offline. The JTF-GNO
spokesman said at the time that the increase in threat conditions had
no relation to the attack against NWC.
