Dark Reading is part of the Informa Tech Division of Informa PLC

This site is operated by a business or businesses owned by Informa PLC and all copyright resides with them.Informa PLC's registered office is 5 Howick Place, London SW1P 1WG. Registered in England and Wales. Number 8860726.

Application Security

2/20/2017
12:00 PM
Derek Melber
Derek Melber
Commentary
Connect Directly
Twitter
LinkedIn
RSS
E-Mail vvv
50%
50%

Controlling Privileged Access To Prevent Rogue Users In Active Directory

Knowing which of your employees have which privileges is the first step to staying safe.

Often, a rogue user is an internal employee who has been granted privileges that he or she shouldn't have. Controlling privileges for your Windows servers, domain controllers, and Active Directory environment is key to limiting what your users can do. The problem is knowing who has privileges and how to restrict those privileges.

But there is a solution! First, you need to report on each area that grants privileged access to ensure the privileges are correct. If they are not correct, simply set the privileges to the appropriate level.

The following is a list of security controls that grant privileges within your Microsoft environment:

  • Group membership (domain admins, enterprise admins, Exchange admins, etc.)
  • User rights (backup files and folders, change system time, system shutdown, etc.)
  • File and folder permissions (access control lists for databases, IP files, etc.)
  • Delegation (Active Directory, Group Policy, etc.)
  • Service access control lists (stop, start, manage) 

To successfully secure your privileged access, have a process and stick to it. Following the steps illustrated in Figure 1 will allow you to get control of privileged access.

Privileged access security control process. (Source: the author.)
Privileged access security control process. (Source: the author.)

1. Report on what security settings are in place. This allows you to make corrections where needed.

2. Analyze the information in the reports that you obtain. Ideally, you should evaluate every area of privileged access to ensure that only the correct users have this level of access to your Windows Servers, domain controllers, and Active Directory.

3. Once you have decided on which security settings to implement, configure them. Usually, Group Policy will be the method to deploy your security controls, but you might also use other Active Directory tools such as Active Directory Users and Computers.

If you stop at just securing your environment, you will never know if anything changes. So, to ensure that a privileged access doesn't change without your knowledge, you need to monitor and alert on changes that occur.

4. Monitor and track all changes that occur to privileged access within your Microsoft environment. This will give you reporting and alerting capabilities.

5. For all of the security settings that can allow vulnerabilities, attacks, and malicious actors to enter your environment, have systems in place to alert you via email when changes to privileges occur.

Once you get control of privileged access for your Windows infrastructure, you will have reduced your attack surface and dramatically increased security for your organization.

Related Content:

Derek Melber is the technical evangelist for ManageEngine, a division of Zoho Corporation. As one of only a handful of Microsoft Group Policy MVPs, Derek helps Active Directory administrators, auditors, and security professionals understand the finer points of how to manage, ... View Full Bio
Comment  | 
Print  | 
More Insights
Comments
Oldest First  |  Newest First  |  Threaded View
kuingul
50%
50%
kuingul,
User Rank: Apprentice
2/21/2017 | 3:00:32 AM
Cure cause as well as symtopms
Just saying that alerts and reports on important security events that lead to overpriveleging users is a great thing to do and it definitely should be done, but it's a bit of taking care of the symptoms, not the causes.

IMO, it's equally (if not more) important to automate things like user lifecycle management, group membership management and other stuff like that. You can do that in a lot of different ways starting from a buch of PowerShell scripts to fully-featured 3rd party solutions like Adaxes or similar.

That is because most of the overprivileging happens because somebody makes a mistake and adds a user to a wrong group. Automation eliminates such things. It's also cool to add approvals that practically send an alert to an admin or another authority before overprivileging happens rather than after like an alert does.
Cybersecurity Team Holiday Guide: 2019 Gag Gift Edition
Ericka Chickowski, Contributing Writer,  12/2/2019
Register for Dark Reading Newsletters
White Papers
Video
Cartoon Contest
Current Issue
Navigating the Deluge of Security Data
In this Tech Digest, Dark Reading shares the experiences of some top security practitioners as they navigate volumes of security data. We examine some examples of how enterprises can cull this data to find the clues they need.
Flash Poll
Twitter Feed
Dark Reading - Bug Report
Bug Report
Enterprise Vulnerabilities
From DHS/US-CERT's National Vulnerability Database
CVE-2019-19647
PUBLISHED: 2019-12-09
radare2 through 4.0.0 lacks validation of the content variable in the function r_asm_pseudo_incbin at libr/asm/asm.c, ultimately leading to an arbitrary write. This allows remote attackers to cause a denial of service (application crash) or possibly have unspecified other impact via crafted input.
CVE-2019-19648
PUBLISHED: 2019-12-09
In the macho_parse_file functionality in macho/macho.c of YARA 3.11.0, command_size may be inconsistent with the real size. A specially crafted MachO file can cause an out-of-bounds memory access, resulting in Denial of Service (application crash) or potential code execution.
CVE-2019-19642
PUBLISHED: 2019-12-08
On SuperMicro X8STi-F motherboards with IPMI firmware 2.06 and BIOS 02.68, the Virtual Media feature allows OS Command Injection by authenticated attackers who can send HTTP requests to the IPMI IP address. This requires a POST to /rpc/setvmdrive.asp with shell metacharacters in ShareHost or ShareNa...
CVE-2019-19637
PUBLISHED: 2019-12-08
An issue was discovered in libsixel 1.8.2. There is an integer overflow in the function sixel_decode_raw_impl at fromsixel.c.
CVE-2019-19638
PUBLISHED: 2019-12-08
An issue was discovered in libsixel 1.8.2. There is a heap-based buffer overflow in the function load_pnm at frompnm.c, due to an integer overflow.