IT Baseline Protection Manual - The Information Warfare Site

Safeguard Catalogue - Hardware & Software Remarks
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S 4.111 Secure configuration of the RAS system
Initiation responsibility: Head of IT Section, IT Security Management
Team
Implementation responsibility: Administrator
The functioning and security of a RAS system are essentially determined by
the configuration parameter settings. However, since a RAS system does not
consist of only one component which has to be configured, the overall
configuration is naturally a lot more complex. Due to this complexity,
configuration errors which could reduce the security of the system as a whole
can easily occur. Uncoordinated changes of one configuration parameter on a
component can thus interact with the other components in such a way as to
prevent error-free operation. In extreme cases the security of the LAN could
even be impaired.
Since the configuration of a RAS system is generally subject to changes over
time (e.g. due to changes in personnel, new operational scenarios, system
enhancements etc.), it cannot be assumed that there is only one secure (and
static) configuration which is defined once and never changed afterwards. On
the contrary, the configuration is likely to undergo a series of version changes.
It is the job of the administrators who are responsible for the RAS system to
ensure that only secure versions of the system configuration are defined and
that when the system configuration settings are changed, the new
configuration is also secure.
In general, the following configuration categories may be distinguished:
- The default configuration comprises the default parameter settings defined
by the vendor. This will normally not be secure enough and should
therefore not be used.
- After installation and prior to initial operation, the default configuration
must be converted to a secure initial configuration by the administrators.
Here the settings should be as restrictive as possible so that only authorised
administrators can effect changes in order, for example, to define an initial
operational configuration which implements the planned security concept.
- The secure operational configurations are the result of configurations
made during ongoing operations. Regular checks must be made here to see
whether any new security weaknesses which have come to light inflict
modifications (see also S 2.35 Obtaining information on security
weaknesses of the system).
- Finally, secure fallback configurations should be defined and documented
as part of contingency planning. These are also used to maintain security
where operational capability is reduced. Normally several emergency
situations are defined during contingency planning. It is recommended that
an appropriate fallback configuration is specified for each of the defined
situations. In the simplest case the fallback configuration simply means
that access to the RAS system is blocked.
To ensure that the configuration is secure, the following points should be
noted when making the configuration settings.
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IT-Baseline Protection Manual: Oktober 2000
Default settings must be
modified