Active Directory (AD) is a critical component of many organizations’ infrastructure, enabling centralized management of users, computers, and services. However, a recent report by NVISO Labs sheds light on the potential vulnerabilities that arise from misconfigurations in AD implementations. This article aims to provide a comprehensive overview of the misconfigurations identified in the report and their implications for organizations.
Misconfiguration Possibilities
The NVISO Labs report highlights several common misconfigurations that organizations may encounter when implementing Active Directory. These misconfigurations can create footholds for threat actors to infiltrate organizations and potentially compromise their sensitive assets.
Delegated Administrator Account Impersonation
One of the alarming risks highlighted in the report is the potential for attackers to gain access to delegated administrator accounts. If successful, threat actors can impersonate these accounts and move laterally within the network, swiftly compromising the domain. The consequences of such compromise could be severe, as it grants the attacker extensive privileges and access to critical resources.
Kerberoasting Attack
Under specific conditions, a misconfigured Active Directory environment can fall prey to a kerberoasting attack. If AES encryption is not enabled on service accounts and RC4 is not explicitly disabled, threat actors gain the ability to request a Kerberos ticket for a specific Service Principal Name (SPN) and subsequently brute force its password. This attack vector underscores the importance of robust encryption configurations to protect against malicious activities.
Abuse of Print Spooler Service
The print spooler service, responsible for managing the printing process, can inadvertently become a tool for threat actors. Through its abuse, attackers can gain access to the hash of the KRBTGT account, which has far-reaching implications as it handles all Kerberos requests in the domain. This misconfiguration highlights the importance of securing and monitoring critical services integral to the Active Directory (AD) infrastructure.
Machine Account and PKI Exploitation
Machine accounts, which represent computers or devices connected to the domain, possess specific attributes that store relevant device information. By exploiting the presence of a Public Key Infrastructure (PKI) in the domain, attackers can utilize the default Machine certificate template to execute a DCSync attack. This attack enables the extraction of hashes for all users and computers in the domain, significantly compromising its security.
Vulnerability of GPO Settings
Group Policy Objects (GPOs) play a crucial role in ensuring security controls and configurations. However, the report warns that modifications to GPO settings are often only applied when new or changed, thereby opening a window of opportunity for threat actors. By modifying a registry key typically managed through a GPO, attackers can disable specific security measures and bypass necessary protections.
Weak Passwords and Service Accounts
The NVISO Labs report also highlights the prevalent issue of weak password policies for service accounts. Additionally, administrators may set easily brute-forceable passwords, further increasing the risk. These weak passwords grant threat actors an advantage in their attempts to exploit vulnerabilities in AD implementations.
Importance of the KRBTGT Account
The KRBTGT account, which is a default account found in all Active Directory domains, plays a crucial role in handling Kerberos requests. Compromising this account could result in unauthorized access across the entire domain, making it a prime target for attackers. Organizations must acknowledge the importance of securing this account and implementing protective measures.
The comprehensive report by NVISO Labs brings to light the variety of misconfiguration possibilities in Active Directory environments. Organizations must take note of these vulnerabilities and proactively address them through effective strategies and practices. By implementing robust security measures and staying informed about emerging threats, organizations can fortify their Active Directory infrastructure against threat actors intent on exploiting misconfigurations.