Golden Ticket Attack – What It Is & How to Prevent It?

Definition – A malicious cyberattack known as a “Golden Ticket attack” aims to obtain user information kept in Microsoft Active Directory (AD) in order to acquire virtually unrestricted access to an organization’s domain (devices, files, domain controllers, etc). In order to access the AD, it takes advantage of flaws in the Kerberos identity authentication protocol, which lets an attacker circumvent standard authentication.

Employees are already entering into company systems using their own devices and networks, expanding the attack surface beyond the traditional perimeter as more businesses move both to the cloud and a remote-first environment. This has raised the possibility that hackers will be able to access a network and launch a Golden Ticket attack.

History of Golden Ticket Attack

Golden ticket assaults started out with good intentions but have subsequently been perverted to serve more sinister objectives. Their tale begins with Benjamin Delpy, a French researcher who sought to expose the flaws in Microsoft’s Active Directory. Software called Mimikatz, developed by Delpy assisted penetration testers in gathering enormous volumes of user data. Additionally, Mimikatz included forging techniques that allowed it to get beyond encryption barriers.

Due to the fact that it takes advantage of a flaw in the Kerberos authentication system, this cyberattack is known as the “Golden Ticket.” The attack is a Golden Ticket that allows unlimited access, just like in the book and movie Charlie and the Chocolate Factory, which gives the attack its name, but instead of a well-guarded candy factory, it’s to get past a company’s cybersecurity and access its resources, files, computers, and domain controllers.

Modus Operandi of Golden Ticket Attack

Typically, Kerberos authentication protects and verifies a user’s identity using a key distribution center. By verifying the user’s identity and issuing them a ticket for access, this method aims to avoid the need for multiple credential requests to the user. The user will be connected to the service server by the ticket-granting server, or TGS, located in the distribution center. All validated users’ passwords are stored in the Kerberos database. The initial user authentication is carried out via the authentication server, or AS. The user receives a Kerberos Ticket Grant Ticket, or TGT, which serves as authentication evidence if AS is validated.

Now, let’s understand how attackers perform such a type of attack.

The fully qualified domain name, the domain’s security identification, the KRBTGT password hash, and the username of the account the attacker intends to access are required for a Golden Ticket assault. The procedures that an attacker takes to obtain this knowledge and then execute the attack are described below.

Step 1: Conduct an investigation. The system must already be accessible to the attacker. Phishing emails are frequently used as a first point of entry into the system. Attackers will then look into the situation and acquire information, including the website name.

Step 2: Steal Access. After gaining entry to the domain controller, an attacker will take the NTLM hash of the Active Directory Key Distribution Service Account (KRBTGT). They might employ strategies like Pass-the-Hash (PtH), which does not necessitate password cracking like previous attempts at credential theft do.

Step 3: Launch the Attack. Once the attacker obtains the KRBTGT password, they can obtain a TGT, which grants them access to the domain controller and authenticates the server. The TGTs additionally give the attacker unrestricted access to resources, enabling them to delegate any domain-related tasks to others and create tickets.

Step 4: Maintain Access: This kind of attack is frequently undetected, and the ticket can be made valid for up to 10 years. In order to further avoid detection, attackers typically adjust the tickets’ validity periods to be shorter.

Golden Ticket Attacks: How to Spot Them?

Hackers cleverly trick the Kerberos system. Typically, the most challenging aspect of a Golden Ticket assault is obtaining the TGT password hash. There are various ways a hacker may approach obtaining the hash. The hacker goes to additional lengths to steal the password hash because of its significance. A cybercriminal might employ the following techniques.

• Using outdated software Mimikatz, the piece of software that gave rise to the golden ticket attack is ideal for gathering data, especially confidential information. It is a helpful tool for penetration testing, but hackers also utilize it.
• Gaining access to a workstation. Never underestimate the lengths to which certain criminals would go, including workplace espionage, in order to achieve their objectives. Once a user has administrative rights, whether it was obtained legally or as a result of office intrigue, they can access the disc drive and look for credentials that are protected by administrative permissions.
• Tracking down the NTDS.DIT file. All user password hashes for a given domain are kept in this database. A duplicate of the file may be located at each domain controller, and it contains a wealth of credentials for dedicated hackers.

The phrase “golden ticket,” which alludes to the freedom a hacked TGT can bring, refers to the cybercriminal’s ability to access any encrypted data once they have the password hash.

Methods to Protect Yourself from Golden Ticket Attack

There are various traditional security procedures that are essential to prevent Golden Ticket attacks. Attacks like the Golden Ticket require the environment to already be compromised because they are post-exploitation attacks. The best practices listed below can aid in limiting access for intruders.

Tip 1: Make Active Directory secure

An infected endpoint or workload might put the entire company at risk of a catastrophic failure. Assisting in the protection of AD and identities, zero trust enforcement—never trust, always verify—guarantees that users have been continually validated and approved before getting access to any data.

The Golden Ticket attack necessitates visibility into user access; the principle of least privilege (POLP) can help secure AD and thwart a Golden Ticket assault. This security principle guarantees that users only receive the access privileges required for performing their job duties.

Tip 2: Concentrate on preventing credential theft.

Make sure that staff members are trained to recognize phishing efforts to stop attackers from getting early access. Phishing emails are a part of Step 1 of how a Golden Ticket assault is carried out. Tools for IT hygiene help guarantee that all credentials are secure and passwords are changed frequently so that an attack on a compromised system can be identified and prevented.

FAQs

Q- What is a Golden Ticket attack?

An advanced hack known as a “Golden Ticket Attack” takes use of the Kerberos authentication mechanism, which is frequently utilized in Windows systems. In order to obtain unauthorized access to a network, it entails forging a Ticket Granting Ticket (TGT).

Q- What’s a Golden Ticket exactly?

A Golden Ticket is essentially a counterfeit TGT that gives an attacker free access to network resources by posing as any user or service within a domain.

Q- How are Golden Tickets made?

By getting the hash of the Key Distribution Centre Service Account (krbtgt) and utilizing it to produce TGTs with random privileges, attackers are able to create a Golden Ticket.

Q- How is the krbtgt hash obtained by an attacker?

The krbtgt hash can be obtained by attackers in a number of ways, including by using pass-the-hash methods, exploiting vulnerabilities, or extracting it from domain controllers.

Q- What might happen if the Golden Ticket Attack is successful?

An attacker can gain complete access to a network’s resources and sensitive data by successfully circumventing all authentication and permission procedures through this attack. Data breaches, lateral movement, and significant harm to an organization’s security can result from this.

Q- How can an organization respond to a suspicion of a Golden Ticket Attack?

An organization should isolate impacted systems, reset passwords for compromised accounts, and look into the breach’s origin if they believe they have been the victim of this attack. In order to stop similar attacks in the future, it’s also critical to report the occurrence to the relevant authorities and carry out a comprehensive post-incident review.