Page 324 - (ISC)² CISSP Certified Information Systems Security Professional Official Study Guide

administrator might want to downgrade the tape to unclassified. The
organization would identify trusted procedures that will purge the tape

of all usable data. After administrators purge the tape, they can then
downgrade it and replace the labels.

However, many organizations prohibit downgrading media at all. For
example, a data policy might prohibit downgrading a backup tape that
contains top secret data. Instead, the policy might mandate destroying
this tape when it reaches the end of its lifecycle. Similarly, it is rare to

downgrade a system. In other words, if a system has been processing
top secret data, it would be rare to downgrade it and relabel it as an
unclassified system. In any event, approved procedures would need to
be created to assure a proper downgrading.

If media or a computing system needs to be downgraded

to a less sensitive classification, it must be sanitized using
appropriate procedures as described in the section “Destroying
Sensitive Data” later in this chapter. However, it’s often safer and
easier just to purchase new media or equipment rather than follow

through with the sanitization steps for reuse. Many organizations
adopt a policy that prohibits downgrading any media or systems.

Handling Sensitive Information and Assets

Handling refers to the secure transportation of media through its
lifetime. Personnel handle data differently based on its value and
classification, and as you’d expect, highly classified information needs
much greater protection. Even though this is common sense, people
still make mistakes. Many times, people get accustomed to handling
sensitive information and become lackadaisical with protecting it.

For example, it was reported in 2011 that the United Kingdom’s

Ministry of Defense mistakenly published classified information on
nuclear submarines, in addition to other sensitive information, in
response to Freedom of Information requests. They redacted the
classified data by using image-editing software to black it out.
However, anyone who tried to copy the data could copy all the text,