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Technology and Process Integration
It is important to evaluate and understand the vulnerabilities in system architectures,
especially in regard to technology and process integration. As multiple technologies and
complex processes are intertwined in the act of crafting new and unique business functions,
new issues and security problems often surface. As systems are integrated, attention should
be paid to potential single points of failure as well as to emergent weaknesses in
service-
oriented architecture (SOA)
. An SOA constructs new applications or functions out of exist-
ing but separate and distinct software services. The resulting application is often new; thus,
its security issues are unknown, untested, and unprotected. All new deployments, especially
new applications or functions, need to be thoroughly vetted before they are allowed to go
live into a production network or the public internet.
Electromagnetic Radiation
Simply because of the kinds of electronic components from which they’re built, many com-
puter hardware devices emit electromagnetic (EM) radiation during normal operation. The
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Chapter 9
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Security Vulnerabilities, Threats, and Countermeasures
process of communicating with other machines or peripheral equipment creates emanations
that can be intercepted. It’s even possible to re-create keyboard input or monitor output
by intercepting and processing electromagnetic radiation from the keyboard and computer
monitor. You can also detect and read network packets passively (that is, without actually
tapping into the cable) as they pass along a network segment. These emanation leaks can
cause serious security issues but are generally easy to address.
The easiest way to eliminate electromagnetic radiation interception is to reduce emana-
tion through cable shielding or conduit and block unauthorized personnel and devices from
getting too close to equipment or cabling by applying physical security controls. By reduc-
ing the signal strength and increasing the physical buffer around sensitive equipment, you
can dramatically reduce the risk of signal interception.
As discussed previously, several TEMPEST technologies could provide protection
against EM radiation eavesdropping. These include Faraday cages, jamming or noise
generators, and control zones. A
Faraday cage
is a special enclosure that acts as an EM
capacitor. When a Faraday cage is in use, no EM signals can enter or leave the enclosed
area.
Jamming
or
noise generators
use the idea that it is difficult or impossible to retrieve a
signal when there is too much interference. Thus, by broadcasting your own interference,
you can prevent unwanted EM interception. The only issue with this concept is that you
have to ensure that the interference won’t affect the normal operations of your devices. One
way to ensure that is to use
control zones
, which are Faraday cages used to block purposely
broadcast interference. For example, if you wanted to use wireless networking within a
few rooms of your office but not allow it anywhere else, you could enclose those rooms in
a single Faraday cage and then plant several noise generators outside the control zone. This
would allow normal wireless networking within the designated rooms but completely pre-
vent normal use and eavesdropping anywhere outside those designated areas.
Summary
Designing secure computing systems is a complex task, and many security engineers have
dedicated their entire careers to understanding the innermost workings of information
systems and ensuring that they support the core security functions required to safely oper-
ate in the current environment. Many security professionals don’t necessarily require an
in-depth knowledge of these principles, but they should have at least a broad understand-
ing of the basic fundamentals that drive the process to enhance security within their own
organizations.
Such understanding begins with an investigation of hardware, software, and firmware
and how those pieces fit into the security puzzle. It’s important to understand the principles
of common computer and network organizations, architectures, and designs, including
addressing (both physical and symbolic), the difference between address space and memory
space, and machine types (real, virtual, multistate, multitasking, multiprogramming, multi-
processing, multiprocessor, and multiuser).
Exam Essentials
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Additionally, a security professional must have a solid understanding of operating states
(single-state, multistate), operating modes (user, supervisor, privileged), storage types (pri-
mary, secondary, real, virtual, volatile, nonvolatile, random, sequential), and protection
mechanisms (layering, abstraction, data hiding, process isolation, hardware segmentation,
principle of least privilege, separation of privilege, accountability).
No matter how sophisticated a security model is, flaws exist that attackers can exploit.
Some flaws, such as buffer overflows and maintenance hooks, are introduced by program-
mers, whereas others, such as covert channels, are architectural design issues. It is impor-
tant to understand the impact of such issues and modify the security architecture when
appropriate to compensate.
Exam Essentials
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