Networking

Bolster security from the inside out

The IT department is responsible for safeguarding company information and systems--but it may also represent a threat to those assets. Strategies such as controlling access to data and audit logs can help avert damage that IT staff members might cause.

The suggestions presented here are part of TechRepublic's Quick Guide: Lock Down Your IT Department. This valuable reference offers insights into the critical security concerns facing today's IT pro, from conducting risk analysis and controlling data access to using tools, technologies, and user policies to guard against internal threats.

Mention the word security in an IT context, and the first thought may be of protecting information assets from plagues of virus threats and malware. But during a TechRepublic roundtable discussion, a panel of IT pros repeatedly expressed a different security concern: How do you protect an organization from its own IT staff? Controlling the damage that could be caused by a disgruntled or an incompetent tech is a serious challenge. Here are a few measures you can take to help make sure that an IT staff member doesn't trash your network or compromise your data.

#1: Control access to data

An obvious way to curtail the power held by IT staff members is to limit their access to data. One approach is to implement application-level security. For instance, let's say that a company wants to make sure that its IT staff can't directly access or manipulate the payroll database. To achieve this degree of protection, it could encrypt the database and allow only the members of the human resources staff to access it once the application development and testing were complete. The developers' accounts would be deleted to ensure access was truly limited to HR personnel, and only the CFO would be authorized to grant access to the application. The CFO's username and password would be stored in a safe in case of emergency.

#2: Limit scope of domain

You can also restrict the power of your IT staff by splitting the network into multiple domains, allowing an individual to be administrator only in certain domains. Under Windows NT, splitting a network into multiple domains pretty much guaranteed that an administrator in one domain couldn't take any action in another without being granted explicit permission. But in Windows 2000 Server and Windows Server 2003, domains exist in a common forest, and a transitive trust exists between them. So even if you create multiple domains, Domain A will automatically trust an administrator from Domain B. The administrator from Domain B won't be able to modify Domain A unless the administrator in Domain B happens to be a member of the Enterprise Admins group. Even so, the simple fact that transitive trusts exist between domains can be a little unsettling. One way to get around this problem is to implement multiple forests within your organization. This greatly increases the complexity of network design and maintenance, but it also increases security. You can configure a trust relationship between a domain in one forest and a domain in another forest, but the trust won't be transitive.

#3: Control access to logs

Another security measure is to enable auditing but to set limits on who can view and clear the audit logs. For example, network administrators might be denied access to the security event logs, with only security staff given access to them. Without administrator credentials, the security team would be unable to create backdoor accounts. The network administrators would be able to create accounts, but they wouldn't be able to cover their tracks by clearing audit log entries.

Since administrators have access to the security logs by default, this approach requires modifying the group policy for the domain. Just open the Default Domain Security Policy console and go to Windows Settings | Security Settings | Local Policies | User Rights Assignment to access the Manage Auditing and Security Log option. Enable the Managing Auditing And Security Log group policy element and assign access only to your security team.

#4: Generate alert triggers

Limiting event logs access is a good start, but if an admin does create a backdoor account, you have to rely on your security team to spot a suspicious log entry. To make the system more foolproof, it would be handy if you could generate an e-mail alert if an administrative account is created. Unfortunately, although you can control what types of events are audited, there is no corresponding alert mechanism. Furthermore, the auditing feature doesn't differentiate between the creation of an account with administrative access and a basic user account, increasing the likelihood that the security team won't notice or be concerned about the corresponding log entry.

One third-party solution that does a good job of alerting you to potential security breaches is GFI's LANguard Network Security Scanner. Using LANguard, you can scan the network to see which shares, accounts, permissions, etc., exist. After you verify that the current settings are valid, you can create a schedule for future scans. After a scan runs, LANguard can compare the results against the results of the previous scan and look for discrepancies. If a new administrative account or network share has been created, the product can send you an alert via e-mail.

About Jody Gilbert

Jody Gilbert has been writing and editing technical articles for the past 25 years. She was part of the team that launched TechRepublic and is now Feature Editor for Tech Pro Research.

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