(ISC)2 CISSP Certified Information Systems Security Professional Official Study Guide. Mike Chapple
tied to those roles. This policy defines a level of acceptable performance and expectation of behavior and activity. Failure to comply with the policy may result in job action warnings, penalties, or termination.
In addition to employment agreements, there may be other security-related documentation that must be addressed. One common document is a nondisclosure agreement (NDA). An NDA is used to protect the confidential information within an organization from being disclosed by a current or former employee. Violations of an NDA are often met with strict penalties. Throughout a worker's employment, they may be asked to sign additional NDAs as their job responsibilities change and they are needing to access new sensitive, proprietary, or confidential assets. When an employee leaves the organization, they should be reminded of their legal obligation to maintain silence on all items covered by any signed NDAs. In fact, they may be required to re-sign the NDA upon departure as a means to legally confirm that they are fully aware of their legally recognized obligation to maintain trade secrets and other confidential information.
Employee Oversight
Throughout the employment lifetime of personnel, managers should regularly review or audit the job descriptions, work tasks, privileges, and responsibilities for every staff member. It is common for work tasks and privileges to drift over time. Drifting job responsibilities or privilege creep can also result in security violations. Excess privileges held by a worker represent increased risk to the organization. That risk includes the greater chance for mistakes to damage asset confidentiality, integrity, and availability (CIA) outside of the worker's actual responsibilities, greater ability for a disgruntled worker to cause harm on purpose, and greater ability for an attack that takes over a worker's account to cause harm. Reviewing and then adjusting user capabilities to realign with the principle of least privilege is a risk reduction strategy.
For some organizations, mostly those in the financial industry, a key part of this review process is enforcing mandatory vacations. Mandatory vacations are used as a peer review process. This process requires a worker to be away from the office and without remote access for one to two weeks per year. While the worker is on the “vacation,” a different worker performs their work duties with their actual user account, which makes it easier to verify the work tasks and privileges of employees while attempting to detect abuse, fraud, or negligence on the part of the original employee. This technique often works better than others since it may be possible to hide violations from other accounts, but it is very difficult to commit violations and hide them from the account used to perform them.
Other user and worker management and evaluation techniques include separation of duties, job rotation, and cross-training. These concepts are discussed in Chapter 16.
When several people work together to perpetrate a crime, it's called collusion. Employing the principles of separation of duties, restricted job responsibilities, mandatory vacations, job rotation, and cross-training reduces the likelihood that a coworker will be willing to collaborate on an illegal or abusive scheme because of the higher risk of detection. Collusion and other privilege abuses can also be reduced through strict monitoring of special privileges and privileged accounts, such as those of an administrator, root, and others.
For many job positions that are considered sensitive or critical, especially in medical, financial, government, and military organizations, periodic revaluation of employees may be needed. This could be a process that is just as thorough as the original background check and investigation performed when the individual was hired, or it may require performing only a few specific checks to confirm consistency in the person's qualifications as well as researching for any new information regarding disqualifications.
User behavior analytics (UBA) and user and entity behavior analytics (UEBA) are the concepts of analyzing the behavior of users, subjects, visitors, customers, and so forth for some specific goal or purpose. The E in UEBA extends the analysis to include entity activities that take place but that are not necessarily directly linked or tied to a user's specific actions, but that can still correlate to a vulnerability, reconnaissance, intrusion, breach, or exploit occurrence. Information collected from UBA/UEBA monitoring can be used to improve personnel security policies, procedures, training, and related security oversight programs.
Offboarding, Transfers, and Termination Processes
Offboarding is the reverse of this onboarding process. Offboarding is the removal of an employee's identity from the IAM system once that person has left the organization. But offboarding can also be an element used when an employee transfers into a new job position at the same organization, especially when they are shifting between departments, facilities, or geographic locations. Personnel transfers may be treated as a fire/rehire rather than a personnel move. This depends on the organization's policies and the means they have determined to best manage this change. Some of the elements that go into making the decision as to which procedure to use include whether the same user account will be retained, if their clearance will be adjusted, if their new work responsibilities are similar to the previous position, and if a “clean slate” account is required for auditing purposes in the new job position.
When a full offboarding is going to occur, whether as part of a fire/rehire transfer, a retirement, or a termination, this can include disabling and/or deleting the user account, revoking certificates, canceling access codes, and terminating other specifically granted privileges. It is common to disable accounts of prior employees in order to retain the identity for auditing purposes for a few months. After the allotted time, if no incidents are discovered in regard to the ex-employee's account, then it can be deleted from the IAM completely. If the account is deleted prematurely, any logged events that are of a security concern no longer point to an actual account and thus can make tracking down further evidence of violations more complicated.
The offboarding process may also include informing security guards and other physical facility and property access management personnel to disallow entry to the ex-employee in the future.
The procedures for onboarding and offboarding should be clearly documented in order to ensure consistency of application as well as compliance with regulations or contractual obligations. Disclosure of these policies may need to be a standard element of the hiring process.
When an employee must be terminated or offboarded, numerous issues must be addressed. A strong relationship between the security department and HR is essential to maintain control and minimize risks during termination.
Terminations are typically unpleasant processes for all involved. However, when well planned and scripted, they might be elevated to a neutral experience. The intent of a termination policy is to reduce the risk associated with employee termination while treating the person with respect. The termination meeting should take place with at least one witness, preferably a higher-level manager and/or a security guard. Once the employee has been informed of their release, they should be reminded of the liabilities and restrictions placed on the former employee based on the employment agreement, NDAs, and any other security-related documentation. During this meeting, all organization-specific identification, access, or security badges as well as devices, cards, keys, and access tokens should be collected (Figure 2.1). The termination of an employee should be handled in a private and respectful manner. However, this does not mean that precautions should not be taken.
For nonvoluntary terminations where there is a perceived risk of a confrontation, the termination