User Manual

Cybersecurity Basics
System Security
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changed during the engineering phase, the system is at high risk, because the hacker
can use it to install malicious software with administrator privileges.
A control or countermeasure is put in place to mitigate the risk and can include HW
or SW procedures, for example, a system with default passwords can be isolated from
the rest of the system to reduce the likelihood of being accessed by an attacker.
Figure 1: Threat and Risk Terminology
1.3 System Security
As explained in the introduction, every modern building automation system must
ensure an adequate level of Cybersecurity protection. It is, however, impossible to
reach a complete level of security, so that there is always a residual risk. The cost of a
counter measure must not exceed the potential damage it can provide. In any case,
the system owner must understand the residual risk and decide if it is acceptable for
the business.
It is important to adopt a systematic view of the security requirements, so that the
effectiveness of the controls is evaluated as a whole, rather than addressing every
component separately. In particular, compensatory counter measures can be
employed to mitigate the vulnerabilities of given subsystems so that the overall
desired security level is achieved.
It is also important that the different players involved contribute to the system
(manufacturers, system integrators and operators) according to their specific roles.
The responsibility of the manufacturers is to deliver security-capable products, up to
the level specified in their product documentation. The integrators are responsible to
design and deploy the solution according to the security specifications of the operator
and to respect the intended operational environments of used products. Finally, the
system operators are responsible for ensuring that the security is kept up to date
within the lifetime of the solution.
Maintaining the security of the solution requires establishing a continuous security
program framework that periodically assesses the desired target security level, the
risks of the system, the status and effectiveness of deployed controls and implements
corrective measures.