In many companies, the finance department’s shared folder is open to everyone, several employees were added to the Domain Admins group for “a temporary task”, and someone who moved from sales to the warehouse three years ago still has access to the sales files. None of this is malicious; access simply builds up over time. The result is dangerous, though: if one of these accounts is hacked, the attacker gains access to all of it.
What Does Least Privilege Mean?
Every user, service account or application should have access only to what it needs to do its job, no more, and for no longer than necessary. This principle has three main benefits:
- Limited damage: A hacked account or malware only reaches a small part of the data.
- Fewer human errors: Someone without delete permission cannot accidentally delete a folder.
- Transparency: It is always clear who has access to what, and why.
Step 1: Identify Resources and Their Owners
List your important resources: shared folders, accounting software, shared mailboxes, admin panels and servers. Assign each resource an owner from the business side, for example the finance manager for the finance folders. The resource owner decides who gets access, and the IT department implements it.
Step 2: Grant Access by Role, Not by Person
Instead of granting access to individual users, create a group in Active Directory for each role or need, for example FIN-Read for reading the finance folder and FIN-Modify for editing it. Grant folder permissions to the group and add users to the group. With this approach:
- A new employee gets all the access they need within minutes by joining their role’s groups.
- A transfer or departure is handled simply by changing group memberships.
- Reporting on who has access to what becomes simple.
Everyone or Domain Users with Full Control on shared folders is one of the most common problems. Even users who need to edit files usually need Modify, not Full Control.
Step 3: Minimize Administrative Access
- Regular users should not have admin rights on their own computers, and software installation should go through the IT department.
- Membership in powerful groups such as Domain Admins should be kept to a minimum and reviewed regularly.
- Service accounts, such as those used by backup software or scanners, should have only the access they need and should be dedicated accounts rather than domain admin accounts.
- Access for contractors and external support providers should be temporary and have an end date.
Step 4: Periodic Review
Every three or six months, send the membership lists of important groups to each resource owner for approval. Also, when an employee changes roles, remove the access of their previous role rather than just adding the new access. This is exactly where most access buildup comes from.
Common Mistakes
- Shared accounts where several people use one username, so nobody knows who did what
- Granting admin rights to fix a problem quickly and forgetting to take them back
- User roles in the accounting software that define everyone as “system administrator”
Checklist
- Important resources and the owner of each are identified.
- Access is granted through groups, not directly to individuals.
- Regular users are not administrators of their own computers.
- Domain Admins members are limited and known.
- Contractor access has an end date.
- Access is reviewed periodically.
ITPlus724 engineers can review the current access rights on your domain and shared folders and implement an organized, role-based structure.