separation of duties in information technology

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    Separation of Duties in Information TechnologyJohn Gregg, Michael Nam, Stephen Northcutt and Mason Pokladnik

    Separation of duties is a classic security method to manage conflict of interest, the appearance of conflict of

    interest, and fraud. It restricts the amount of power held by any one individual. It puts a barrier in place to prevent

    fraud that may be perpetrated by one individual. Fraud will still occur if there is collusion. To be certain that you have

    identified all separation of duties issues, you will first need to create an information flow diagram for every function

    within each area of the organization. However common sense can help identify a large number of situations where

    separation of duties is appropriate. For instance, positions that handle money, valuable items, and new andattractive items (think iPad after it first came out), require a number of controls. Although there are a number of

    similar controls among organizations, specific controls are relatively different between industries. There is no

    complete matrix that may be applied to all organizations. separation of duties within each company is unique. Since

    separation of duties equates to additional cost because it often increases head count, a risk assessment should first

    be performed to determine whether it is necessary, or whether compensating controls are adequate. As you are

    aware, management may decide to accept, reject, or divert the risk instead of controlling the risk through separation

    of duties. It is a balance between the cost and the amount of risk being considered and addressed. Once this is

    decided, management may determine where separation of duties will be applied.

    Note: John Gregg from UC Davis, developed a self assessment for determining risk related to separation of duties, itis available here.[1]

    To expand on positions concerning money: in general, one person should indicate the action related to money

    inflow or outflow, another verifies that action has happened or causes the action to happen. It is very common for

    accounting divisions to have this separation. Examples: A salesperson may take orders, but someone else marks

    the order paid. The fulfillment department ships the product. The accounts receivable clerk matches the customer

    order to the shipment sent before charging the customer. A purchasing agent may have the authority to bind the

    company to purchase orders up to a specific amount. Their supervisor should be required to approve purchase

    order over that amount. After the product is received, the accounts payable clerk matches the purchase order, bil

    of lading, and invoice before payment is made.

    Internal and External Auditors perform similar functions. To have External Audit review the internal controls and

    financial statements of a company is not a separation of duties issues. External Audit is an independent party

    that reviews the work of Internal Audit, internal controls, and financial records of the company. External Audit's

    assessment is for the general shareholders, while the Internal Audit's assessment is primarily for management

    and the board of directors.

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    Building contractors and their subs do the work, county impartial inspectors evaluate the work to ensure that it

    meets the current building code. In fact, in industry there are numerous examples of "doers and inspectors".

    Separation of duties in Information TechnologyThe technology group should understand the basic separation of duties issues within the technology area as well as

    the principle of least privilege. However, technology does not normally have the expertise to determine the

    separation of duties issues within the business. Although conflicting access rights may be a cause for concern, it is

    not technology's responsibility to identify these separation of duties issues. However, following the reasonable

    person rule, technology does have the responsibility to bring a separation of duties issue to management attention

    when they observe them. The audit function usually has more training and expertise to map business logic to

    information flow and suggest where separation of duties makes sense. Ultimately, it is business management's

    responsibility to adequately address separation of duties issues. For daily operational purposes, Compliance may be

    sought to review user access rights to address separation of duties concerns. Internal Audit would review user

    access during audits for separation of duties issues. Note that Internal Audit would not do it on a daily operational

    basis as it would become a separation of duties issues for Internal Audit. Where Internal Audit performs this function

    Internal Audit will not have the appearance of being objective during their audit.

    Intellectual property is the lifeblood of anIntellectual property is the lifeblood of anIntellectual property is the lifeblood of anIntellectual property is the lifeblood of anorganization and process should be designed toorganization and process should be designed toorganization and process should be designed toorganization and process should be designed to

    protect it. Some specific tips:protect it. Some specific tips:protect it. Some specific tips:protect it. Some specific tips:Software developers should never have access to production systems. Production systems should not have

    compilers installed. A configuration management board or equivalent should be involved in the decision to place

    code that has been developed into a production environment. No code should ever be installed in a production

    environment that has not been approved. As a general principle development and production should always be

    separate with no crossover (at a minimum, the root/administrator password on development systems should not

    work on production systems. Better practice is not to allow developer accounts on production systems and to use

    network access control so that developer VLANS cannot access production systems other than office automation

    production systems so they can read their email.) Developers may be granted access to production for

    emergency changes using pre-established accounts for this purpose at the time of need. Controls need to beimplemented to administer distribution. Emergency change procedures should only be initiated for operational

    problems occurring at night where a process must be completed and developer intervention is required. Additional

    controls will need to be implemented to ensure that changes are tested and approved properly. This problem is

    not unique to software development. Change control can be applied to many operational aspects of IT as well,

    such as having a manger approve firewall rule changes before they are applied.

    Source code, or other intellectual property repositories should always have a monitoring counter to detect

    excessive use. For instance, SANS might have a courseware repository. Since courses are commonly six days,

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    but there might also be lab manuals, the counter might be set to ten. When an instructor is preparing to teach a

    class, they download the latest version of the courseware for each day. However, if they download more than ten

    files from the repository over a certain span of time, an alert might be sent to management or it could even trigger

    an account logout.

    Backups are important and we want to encourage backups, but not everyone that has administrator or super user

    privilege should be allowed to create backups since this gives them a copy of all of the intellectual property.

    Approved backup operators should be identified in writing with the appropriate procedures. In general, it is farsafer to use disk replication to an alternate site. Backups made to small tapes that easily fit in a pocket or

    briefcase are the highest risk. Backup tapes may need to be produced for regulatory compliance and should be

    protected in a manner consistent with the sensitivity of the information.

    Outsourced maintenance personnel should be restricted to the systems they are working on. This can be done by

    creating a unique VLAN, or DMZ, or using tools like Exceedium or sometimes referred to as Xceedium. All

    contractors should have contracts that meet the company's privacy requirements, including non-disclosure

    agreements. A vendor management policy and privacy policy should be implemented and enforced. Privacy

    Policy needs to address the data classification of intellectual property.

    Network and Security administrators have the ability to see anything that is sent across the network. Only

    authorized sniffers may be used. Only authorized signature sets may be used. When possible, portable sniffers

    should not be used; use investigation enterprise level devices with a console. Only with written permission should

    the sniffer be a piece of software on the network administrator s laptop; it is highly recommended to have a

    corporate device stored appropriately and checked out for use as needed.

    Database administrators are the hardest position to control. If you want the database to work, all tables probably

    have to join. DBAs should only have DBA authority, not root or administrator. It may be possible to encrypt the

    content of some sensitive fields in the database. Consider tools that manage and audit database access, such

    as Imperva. All activity for accounts with elevated privileges should be logged and reviewed daily by an

    independent party. It should be noted that Oracle has made significant progress in the past few years to allow

    separation of duties.

    To enforce accountability, generic administrative accounts should be disabled - and an alert issued if they are

    used - since generic accounts can be used to bypass role-based access controls. In addition, the principal of

    least privilege suggests that each Administrator and DBA should have two accounts, one with elevated rights and

    one with normal user rights. The normal account should be used to perform mundane functions such as checking

    email, while the account with elevated rights should only be used to perform tasks requiring administrator\\\\super

    user level access. If a process is particularly sensitive, two factor authentication may be used to further ensurethat the person performing the task is the person authorized to do so.

    Logging for systems, network equipment, databases, etc., should be directed to a write-only logging system. The

    logging system should be administered by a group separate from the people responsible for network and systems

    administration, and access to the logging system should be role-based so that administrators may only see the

    logs for their own systems.

    Even if IT is the custodian of the information, employee's may be able to access sensitive information. Two

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    classic examples are contact lists and contracts. If a salesperson is leaving an organization, it is a time honored

    tradition to try to leave with the entire customer contact list. Receiving and providing contracts give a clear

    picture of the revenue and cost structure of an organization. These should be protected not only with digital

    means, but also with physical security protections.

    Positions involving management duties can create conflict of interest or the appearance of same. The CIO or

    other officer responsible for roll out should not have signature authority over security or compliance workers or

    tasks.

    The rich questions to ask are:

    - Can one person destroy or encrypt all (or a significant amount) of the intellectual property?

    - Can one person steal or exfiltrate a significant amount of the intellectual property?

    - Is it possible to access the intellectual property off hours or from the Internet? If so, do we rely on single factor

    authentication, or do we have multi-factor authentication?

    - Do we only focus on the protection of digital information? Even in 2012, a tremendous amount of intellectual

    property gets printed; how is it disposed of?

    ====

    1 http://accounting.ucdavis.edu/refs/Departmental_Risk_Assessment.xls