1. BACHELOR’S THESIS DEFENSE
Protecting Windows Privileged Accounts
BACHELOR’S THESIS DEFENSE
Loc Phan Van IDCR
Supervisor: Ilhan Celebi – Infrastructure Engineer

2. Agenda Introduction Effectiveness of Implementation
Windows Active Directory Security Principles
Define Sensitive Groups
Windows Active Directory Security Development
Best Practices
Conclusions

3. Introduction Background Problems Objectives
Privileged accounts have always become a primary target
It’s like a regular accounts, have a valid set of credentials -> system, network
Windows privileged accounts are complicated compared to other systems
Most popular Operating System, directory service
Due to the complexity -> hard to manage, gets ignored.
Expensive security software
Give administrative principles
Point out sensitive groups
Develop a tool for privileged accounts information gathering
Develop monitoring solution for privileged accounts

4. Effectiveness of implementation
Time line for typical attack scenario
80% from external attacks
75% of attacks take weeks or more (Verizon Report)
$1,2M over a week for recovering (IT Sec Risk Report)

5. Effectiveness of implementation
Detect abnormal behaviors
Alert to Administrators
Extend the time of escalation by applying
RBAC
Tier Model
Secondary
account
Tier-0
Groups
Privileged
Admin
Workstation
Naming
Convention
Privileged
Account
Cleaning-up

6. Windows AD Security Principles
Role based access control
Tier Model
Dealing With Tier-0 Groups
Secondary accounts
Privileged Admin Workstation
Naming Convention
Privileged accounts cleaning-up 1 2 3 4 5 6 +

7. Windows AD Security Principles
Privileged Account Cleaning-up
Implement the data investigation on the AD objects.
Have more focus on Administrative objects (accounts, groups).
Have more focus on Service accounts and check if the services are still running.
Promulgate the policies for those unused objects (delete them or deactivate them).

8. Windows AD Security Development1
Privileged Accounts Information Gathering 2
Privileged Accounts Monitoring

9. Windows AD Security Development1
Privileged Accounts Information Gathering

10. Windows AD Security Development2
Privileged Accounts Monitoring +

11. Windows AD Security Development2
Privileged Accounts Monitoring

12. Best practices Inventory and reduce the number of privileged accounts.
Secondary accounts.
Enforce least privileged for standard user accounts.
Store password securely.
Create a process for on- and off-boarding employees that have privileged accounts.
Eliminate the practice of accounts that have non-expiring passwords.
Password complexity and password age policy.
Implement automated password verification and reconciliation.
Privileged account information gathering.
Proactivity detect malicious behavior.

13. Conclusions Very first stepping stones in Windows Security
Contribute Windows administrative principles
Implement privileged accounts information gathering
Manipulate and develop a monitoring solution
Give best practices
Further work: Dealing with service account

14. Thank you

15. Reviewer’s questions

16. Tier 0 groups Domain Admins
Active Directory group with full admin rights to the Active Directory domain and all computers (default).
Enterprise Admins
Active Directory group with full admin rights to all Active Directory domains in the AD forest and gains this right through automatic membership in the Administrators group in every domain in the forest.
Schema Admins
Members of the Schema Admins group can modify the Active Directory schema. This group exists only in the root domain of an Active Directory forest of domains.
Backup Operators
Local or Active Directory group. AD group members can backup or restore Active Directory and have logon rights to Domain Controllers (default).
Server Operators
Members in the Server Operators group can administer domain servers. This group exists only on domain controllers. By default, the group has no members. Members of the Server Operators group can sign in to a server interactively, create and delete network shared resources, start and stop services, back-up and restore files, format the hard disk drive of the computer, and shut down the computer. This group cannot be renamed, deleted, or moved.
Print Operators
Members of this group can manage, create, share, and delete printers that are connected to domain controllers in the domain. They can also manage Active Directory printer objects in the domain. Members of this group can locally sign in to and shut down domain controllers in the domain.
Account Operators
Active Directory group with default privileged rights on domain users and groups, plus the ability to logon to Domain Controllers.
Administrators
Local or Active Directory group. The AD group has full admin rights to the Active Directory domain and Domain Controllers.

17. Sensitive groups Pre–Windows 2000 Compatible Access
Members of the Pre–Windows 2000 Compatible Access group have Read access for all users and groups in the domain.
Remote Desktop Users
The Remote Desktop Users group on an RD Session Host server is used to grant users and groups permissions to remotely connect to an RD Session Host server. This group cannot be renamed, deleted, or moved. It appears as a SID until the domain controller is made the primary domain controller and it holds the operations master role (also known as flexible single master operations or FSMO).
WinRMRemoteWMIUsers__
In Windows Server 2012, the Access Denied Assistance functionality adds the Authenticated Users group to the local WinRMRemoteWMIUsers__ group. Therefore, when the Access Denied Assistance functionality is enabled, all authenticated users who have Read permissions to the file share can view the file share permissions.
The WinRMRemoteWMIUsers_ group allows running Windows PowerShell commands remotely whereas the Remote Management Users group is generally used to allow users to manage servers by using the Server Manager console.
Protected User
Members of the Protected Users group are afforded additional protection against the compromise of credentials during authentication processes. This security group is designed as part of a strategy to effectively protect and manage credentials within the enterprise. Members of this group automatically have non-configurable protection applied to their accounts.

18. Windows AD Security Principles
Role based access control
Tier Model

19. Windows AD Security Principles
Dealing with Tier-0 Groups
Domain Admins
Enterprise Admins
Schema Admins
Backup Operators
Server Operators
Print Operators
Account Operators
Administrators
One account for normal user activities:
Mail
Internet Browsing
Line of business applications etc.
Separate account for doing administration.
One admin account for each tier
For example:
pe889 [^pe]: for regular user accounts
ad335 [^ad]: for administrative accounts
Secondary accounts

20. Windows AD Security Principles
Privileged Admin Workstation
Role:
Role-<Role Tier>-<Role Name>
Prefix: Role
Role Tier: T0/T1/2
Role Name: Job Function
Role-T2-WorkstationAdmins
Task:
Task-<Target Object Type>-<Operation>-<Target>
Prefix: Task
Target Object Type: AD object type
Operation: Create/Delete/Manage etc.
Target: Short Name for OU/Target
Task-Computer-Create-CORP
Naming Convention