- The most famous form of injection is SQL Injection where an attacker can modify existing database queries. For more information see the SQL Injection Prevention Cheat Sheet. But also LDAP, SOAP, XPath and REST based queries can be susceptible to injection attacks allowing for data retrieval or control bypass.
- Windows DSQuery & LDAP CHEAT SHEET DSQuery Important Options:-s Specify the target domain controller-u Specify a domain user ID-p Specify password-limit Override default 100 item limit (Use ‘ -limit 0’ for ‘no limit’) LDAP Query Format 4VI½ RSXEXMSR (&(objectClass=User)(objectCategory=Person)) is equivalent to (objectClass=User).
- LDAP Injection Cheat Sheet, Attack Examples & Protection Lightweight Directory Access Protocol (LDAP) is an open and vendor-neutral directory service protocol that runs on a layer above the TCP/IP stack. It provides the appropriate mechanism for the implementation of authentication and authorization controls, things that are commonly used while developing intranet and internet (web.
Are you looking for a quick and easy solution to bulk modify Active Directory user attributes?
LDAP (Lightweight Directory Access Protocol) is a software protocol for enabling anyone to locate organizations, individuals, and other resources such as files and devices in a network, whether on the public Internet or on a corporate intranet. LDAP is a 'lightweight' (smaller amount of code) version of Directory Access Protocol (DAP).
Then you are in the right place.
In this post, I’m going to show you the AD Bulk User Update Tool that makes it easy to bulk update active directory user attributes.
This is a GUI tool that updates AD user attributes from a CSV.
Let’s jump right into some examples:
Example 1: Bulk Modify Users Office Attribute
In this example, I’m going to mass update the department attribute for 100 users. If there is a value already present it will get updated.
The AD Bulk User Modify tool uses a CSV file to bulk modify Active Directory user accounts. All you need is the users sAMAccountName and the LDAP attribute you want to modify.
If you are not familiar with LDAP attributes you may want to jump to the LDAP attributes section for a quick overview. I’ve created an LDAP cheat sheet to quickly find the correct LDAP values.
Step 1: Setup the CSV File
The first column of the CSV file needs to be the sAmAccountName followed by the list of users you want to modify. The next column needs to be the attribute you want to modify followed by the value.
TIP: The Active Directory names do not always match the LDAP attribute name. This is how Microsoft designed it. This can be confusing and is why I created a cheat sheet showing the most common Active Directory names to LDAP attribute names. See the end of this post for the cheat sheet.
Looking at the cheat sheet the LDAP attribute for office is physicalDeliveryOffice.
You can see below I have my CSV file setup and ready to import. I’ll just save it to my computer and move to step 2. (You can name the file whatever you want it just needs to be a CSV file).
Step 2: Run AD Bulk User Modify Tool
Now the easy part.
Open the AD User Bulk Update tool, select the CSV file and click run.
As the tool runs through the CSV it displays the progress in the output box.
It’s really fast! It took about 10 seconds to update the office field for 100 users.
Step 3: Verify the changes
This is optional but to verify the change just add the office column to Active Directory Users and Computers.
Now you can easily see your user accounts and the office field.
You can use PowerShell to verify the changes with this command.
Looks great!
I can see the test users account office attribute has been updated to the value I set in the CSV file.
Example 2: Bulk Update User Department and Job Title
In this example, I will update the department and title attribute at the same time. You can modify as many attributes at once as you wish.
Again, if a value is already set it will be overwritten.
I look at the LDAP cheat sheet and see I need attributes department and title.
Now, I’ll setup the CSV file.
Ready to go, I’ll open the tool, select the CSV file and click run.
The tool runs and makes the changes set by the CSV file.
Now I’ll verify the changes in ADUC.
To verify with PowerShell use this command
Perfect!
I just modified the department and job title for 100 users in 15 seconds.
Example 3: Bulk Update User Employee ID & Employee Number
In this example, I’ll update the Employee ID & Employee Number values for my 100 test accounts.
These two values only show up in the attribute editor, the values do not show up on any of the tabs in Active Directory Users and Computers.
The LDAP attribute names are employeeID and employeeNumber.
I’ll update my CSV with the LDAP attribute name and set the values I want.
Now I’ll run the tool to update the attributes.
These two attributes are not available to add as a column in ADUC. So you will need to use PowerShell to mass verify the changes.
Looks good. I can scroll down the list and see the 100 test accounts have been updated.
In about a minutes worth of work, I just updated the employeeid and employeenumber on 100 accounts.
Example 4: Bulk Remove User Attributes
The first three examples I showed you how to mass update user attributes but what if you want to bulk remove user attributes?
No problem.
The process is almost the same, just add the LDAP attribute to the CSV and for the value put remove.
I’ll remove the department and job title values for my 100 test accounts.
Now just run the tool, select the CSV and click run.
I’ll verify the changes in ADUC
Looks good the values have been removed.
To verify with PowerShell use this command.
Bonus! You can remove and update values at the same time.
Understanding the LDAP Attribute Names (LDAP Cheat Sheet)
Active Directory stores details about objects such as users into LDAP attributes. These attributes are basically a key value pair for example:
givenName = Robert
GiveName is the attribute name and Robert is the value.
This is the method Active Directory uses to store details about objects.
Here is where it gets a little confusing and is why I created the LDAP cheat sheet.
The fields names you see in Active Directory Users and computers do not always match the LDAP attribute name.
For example, in ADUC the First Name field has an LDAP attribute value of giveName
Below is a table of the most commonly used ADUC fields and the LDAP attribute mappings. I’ve grouped them based on the ADUC tabs General, Address, Profile, Telephones, and Organization.
You can use this to quickly lookup what LDAP attribute name to setup in the CSV file.
LDAP Attribute Cheat Sheet
This is a downloadable PDF.
The AD Bulk modify tool is not limited to the table above, again those are just common fields. The AD Bulk Modify tool will update any LDAP attribute.
You can use the attribute editor on any account to find other attributes you may need to bulk update.
Screenshot of the attribute editor on an account, this lets you see all the attributes.
Ldap Injection Cheat Sheet
You can also use PowerShell to view the LDAP attributes.
Change username to the account you want to view
Ldap Filter Cheat Sheet
Get-ADUser username -Properties *
Final Thoughts
There comes a time when every administrator faces the need to make bulk changes to Active Directory user accounts. I have faced this challenge several times and have struggled with it in the past. With the AD User Bulk Update Tool this is no longer a problem myself or my team has to deal with. This tool makes it very easy and saves a great amount of time when dealing with modifying user accounts.
This tool is included in the AD Pro Toolkit. You can download a free trial here.
Recommended Tool: SolarWinds Server & Application Monitor
This utility was designed to Monitor Active Directory and other critical services like DNS & DHCP. It will quickly spot domain controller issues, prevent replication failures, track failed logon attempts and much more.
What I like best about SAM is it’s easy to use dashboard and alerting features. It also has the ability to monitor virtual machines and storage.
Running ldapadd or ldapmodify and using the rootdn configured inslapd.conf:
Assumes rootdn is defined something like this:
where the encrypted password was created with slappasswd.
Running ldapsearch using simple authentication and the rootdn. (Passwordswon’t show up in the result unless bind is done this way.)
Prompt for password:
Specifying password on command line:
Make sure SASL stuff is in config. See sample slapd.conf, below. Then,run this command:
Easiest way is via LDIF, in a field. e.g.,
userPassword field defines the password.
Must also configure slapd to look there. See “access to attr=userPassword”in sample config, below.
Sample /etc/openldap/slapd.conf: