Document code:  PRO-0027.06  Security level:  Internal  Effective date:  15/01/2019  ICT Governance  and user of a system should operate using the least set of permissions and privileges  necessary to complete their job. Primarily, this principle limits the damage that can result  from unauthorised, unintentional or improper uses of privileges. A blatant example of the  failure to adhere to the principle of least privilege is logging into Windows as Local  Administrator to read email and browsing Internet. Violations of this principle can also occur  when an individual collects additional access privileges over time 7 .While the principle is more  related to (secure) software development and user access management, it is also applied  in operating system hardening and network access control.  Overall security can be only as effective as the weakest link in the chain from end-to-end.  Thus, the weakest link principle states that the whole chain should be adequately protected  by similar level of protection.  As complexity is often an enemy of security and a friend of attackers, one of security  principles is simplified architecture. Therefore unnecessary complexity, both from a design  perspective and from an implementation perspective, should be avoided and the security  mechanisms should be pervasive, simple, scalable, and easy to manage.  While complexity increases the risk of problems, also the risk of security problems, it cannot  be completely avoided. Also, the simplification may be a conflicting principle with the  defence in depth and least privileges. If the principles have conflicts, a risk driven approach  is applied to find a balance between the principles. As long as new threats and attack methods are evolving, and amount and therefore value  of collected information is increasing, IT security must be continuously improved to sustain  the state at the current, acceptable level. While operational level improvements happen  frequently based on evolution of the threats, continuous improvements cover also mid- and  long-term tactical and strategic security aspects.  All the principles are applied by following the risk driven approach; For example, if a  system stores lot of highly sensitive information, the defense in depth and least privileges  principles are strictly applied. On the other hand, if a system requires lower level of  protection 8 , the principle simplicity and standardization has a main role. Thus, for  example, depth of defense, i.e. required number of independent protection layers,  depends on system criticality and threats targeted.  “ Secure Application Design and Development Guideline ” sets a security  framework and  principles for all ECHA IT projects where new systems or applications are designed or  developed. It defines how security of the product to be developed is considered and  implemented in different phases of the projects. Projects have to include in the  requirements the security measures, based on the result of the risk assessment and take  7  This may happen when employees' job duties change, or they are promoted to a new position, or they transfer  to another unit or directorate. The access privileges required by their new duties are frequently added onto their  already existing access privileges which may no longer be necessary or appropriate.  8 For example development system which doesn’t process or stor e non-public information Page  82  of  92 TEM-0129.01  Uncontrolled copy once printed. Ensure that the right version is in use.  Continuous improvement  Simplicity and standardisation Protect the weakest link 