Modify Authentication Process: Domain Controller Authentication
Other sub-techniques of Modify Authentication Process (9)
Adversaries may patch the authentication process on a domain controller to bypass the typical authentication mechanisms and enable access to accounts. Malware may be used to inject false credentials into the authentication process on a domain controller with the intent of creating a backdoor used to access any user’s account and/or credentials (ex: Skeleton Key). Skeleton key works through a patch on an enterprise domain controller authentication process (LSASS) with credentials that adversaries may use to bypass the standard authentication system. Once patched, an adversary can use the injected password to successfully authenticate as any domain user account (until the the skeleton key is erased from memory by a reboot of the domain controller). Authenticated access may enable unfettered access to hosts and/or resources within single-factor authentication environments.(Citation: Dell Skeleton)
Procedure Examples |
|
Name | Description |
---|---|
Chimera |
Chimera's malware has altered the NTLM authentication program on domain controllers to allow Chimera to login without a valid credential.(Citation: Cycraft Chimera April 2020) |
Skeleton Key |
Skeleton Key is used to patch an enterprise domain controller authentication process with a backdoor password. It allows adversaries to bypass the standard authentication system to use a defined password for all accounts authenticating to that domain controller.(Citation: Dell Skeleton) |
Mitigations |
|
Mitigation | Description |
---|---|
Privileged Account Management |
Privileged Account Management focuses on implementing policies, controls, and tools to securely manage privileged accounts (e.g., SYSTEM, root, or administrative accounts). This includes restricting access, limiting the scope of permissions, monitoring privileged account usage, and ensuring accountability through logging and auditing.This mitigation can be implemented through the following measures: Account Permissions and Roles: - Implement RBAC and least privilege principles to allocate permissions securely. - Use tools like Active Directory Group Policies to enforce access restrictions. Credential Security: - Deploy password vaulting tools like CyberArk, HashiCorp Vault, or KeePass for secure storage and rotation of credentials. - Enforce password policies for complexity, uniqueness, and expiration using tools like Microsoft Group Policy Objects (GPO). Multi-Factor Authentication (MFA): - Enforce MFA for all privileged accounts using Duo Security, Okta, or Microsoft Azure AD MFA. Privileged Access Management (PAM): - Use PAM solutions like CyberArk, BeyondTrust, or Thycotic to manage, monitor, and audit privileged access. Auditing and Monitoring: - Integrate activity monitoring into your SIEM (e.g., Splunk or QRadar) to detect and alert on anomalous privileged account usage. Just-In-Time Access: - Deploy JIT solutions like Azure Privileged Identity Management (PIM) or configure ephemeral roles in AWS and GCP to grant time-limited elevated permissions. *Tools for Implementation* Privileged Access Management (PAM): - CyberArk, BeyondTrust, Thycotic, HashiCorp Vault. Credential Management: - Microsoft LAPS (Local Admin Password Solution), Password Safe, HashiCorp Vault, KeePass. Multi-Factor Authentication: - Duo Security, Okta, Microsoft Azure MFA, Google Authenticator. Linux Privilege Management: - sudo configuration, SELinux, AppArmor. Just-In-Time Access: - Azure Privileged Identity Management (PIM), AWS IAM Roles with session constraints, GCP Identity-Aware Proxy. |
Privileged Process Integrity |
Privileged Process Integrity focuses on defending highly privileged processes (e.g., system services, antivirus, or authentication processes) from tampering, injection, or compromise by adversaries. These processes often interact with critical components, making them prime targets for techniques like code injection, privilege escalation, and process manipulation. This mitigation can be implemented through the following measures: Protected Process Mechanisms: - Enable RunAsPPL on Windows systems to protect LSASS and other critical processes. - Use registry modifications to enforce protected process settings: `HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Lsa\RunAsPPL` Anti-Injection and Memory Protection: - Enable Control Flow Guard (CFG), DEP, and ASLR to protect against process memory tampering. - Deploy endpoint protection tools that actively block process injection attempts. Code Signing Validation: - Implement policies for Windows Defender Application Control (WDAC) or AppLocker to enforce execution of signed binaries. - Ensure critical processes are signed with valid certificates. Access Controls: - Use DACLs and MIC to limit which users and processes can interact with privileged processes. - Disable unnecessary debugging capabilities for high-privileged processes. Kernel-Level Protections: - Ensure Kernel Patch Protection (PatchGuard) is enabled on Windows systems. - Leverage SELinux or AppArmor on Linux to enforce kernel-level security policies. *Tools for Implementation* Protected Process Light (PPL): - RunAsPPL (Windows) - Windows Defender Credential Guard Code Integrity and Signing: - Windows Defender Application Control (WDAC) - AppLocker - SELinux/AppArmor (Linux) Memory Protection: - Control Flow Guard (CFG), Data Execution Prevention (DEP), ASLR Process Isolation/Sandboxing: - Firejail (Linux Sandbox) - Windows Sandbox - QEMU/KVM-based isolation Kernel Protection: - PatchGuard (Windows Kernel Patch Protection) - SELinux (Mandatory Access Control for Linux) - AppArmor |
Multi-factor Authentication |
Multi-Factor Authentication (MFA) enhances security by requiring users to provide at least two forms of verification to prove their identity before granting access. These factors typically include: - *Something you know*: Passwords, PINs. - *Something you have*: Physical tokens, smartphone authenticator apps. - *Something you are*: Biometric data such as fingerprints, facial recognition, or retinal scans. Implementing MFA across all critical systems and services ensures robust protection against account takeover and unauthorized access. This mitigation can be implemented through the following measures: Identity and Access Management (IAM): - Use IAM solutions like Azure Active Directory, Okta, or AWS IAM to enforce MFA policies for all user logins, especially for privileged roles. - Enable conditional access policies to enforce MFA for risky sign-ins (e.g., unfamiliar devices, geolocations). Authentication Tools and Methods: - Use authenticator applications such as Google Authenticator, Microsoft Authenticator, or Authy for time-based one-time passwords (TOTP). - Deploy hardware-based tokens like YubiKey, RSA SecurID, or smart cards for additional security. - Enforce biometric authentication for compatible devices and applications. Secure Legacy Systems: - Integrate MFA solutions with older systems using third-party tools like Duo Security or Thales SafeNet. - Enable RADIUS/NPS servers to facilitate MFA for VPNs, RDP, and other network logins. Monitoring and Alerting: - Use SIEM tools to monitor failed MFA attempts, login anomalies, or brute-force attempts against MFA systems. - Implement alerts for suspicious MFA activities, such as repeated failed codes or new device registrations. Training and Policy Enforcement: - Educate employees on the importance of MFA and secure authenticator usage. - Enforce policies that require MFA on all critical systems, especially for remote access, privileged accounts, and cloud applications. |
User Training |
User Training involves educating employees and contractors on recognizing, reporting, and preventing cyber threats that rely on human interaction, such as phishing, social engineering, and other manipulative techniques. Comprehensive training programs create a human firewall by empowering users to be an active component of the organization's cybersecurity defenses. This mitigation can be implemented through the following measures: Create Comprehensive Training Programs: - Design training modules tailored to the organization's risk profile, covering topics such as phishing, password management, and incident reporting. - Provide role-specific training for high-risk employees, such as helpdesk staff or executives. Use Simulated Exercises: - Conduct phishing simulations to measure user susceptibility and provide targeted follow-up training. - Run social engineering drills to evaluate employee responses and reinforce protocols. Leverage Gamification and Engagement: - Introduce interactive learning methods such as quizzes, gamified challenges, and rewards for successful detection and reporting of threats. Incorporate Security Policies into Onboarding: - Include cybersecurity training as part of the onboarding process for new employees. - Provide easy-to-understand materials outlining acceptable use policies and reporting procedures. Regular Refresher Courses: - Update training materials to include emerging threats and techniques used by adversaries. - Ensure all employees complete periodic refresher courses to stay informed. Emphasize Real-World Scenarios: - Use case studies of recent attacks to demonstrate the consequences of successful phishing or social engineering. - Discuss how specific employee actions can prevent or mitigate such attacks. |
Detection
Monitor for calls to OpenProcess
that can be used to manipulate lsass.exe running on a domain controller as well as for malicious modifications to functions exported from authentication-related system DLLs (such as cryptdll.dll and samsrv.dll).(Citation: Dell Skeleton)
Configure robust, consistent account activity audit policies across the enterprise and with externally accessible services.(Citation: TechNet Audit Policy) Look for suspicious account behavior across systems that share accounts, either user, admin, or service accounts. Examples: one account logged into multiple systems simultaneously; multiple accounts logged into the same machine simultaneously; accounts logged in at odd times or outside of business hours. Activity may be from interactive login sessions or process ownership from accounts being used to execute binaries on a remote system as a particular account. Correlate other security systems with login information (e.g. a user has an active login session but has not entered the building or does not have VPN access).
References
- Microsoft. (2016, April 15). Audit Policy Recommendations. Retrieved June 3, 2016.
- Dell SecureWorks. (2015, January 12). Skeleton Key Malware Analysis. Retrieved April 8, 2019.
- Cycraft. (2020, April 15). APT Group Chimera - APT Operation Skeleton key Targets Taiwan Semiconductor Vendors. Retrieved August 24, 2020..
- Plett, C., Poggemeyer, L. (12, October 26). Securing Privileged Access Reference Material. Retrieved April 25, 2017.
- Microsoft. (2016, April 16). Implementing Least-Privilege Administrative Models. Retrieved June 3, 2016.
- Microsoft. (2016, April 15). Attractive Accounts for Credential Theft. Retrieved June 3, 2016.
- Microsoft. (2013, July 31). Configuring Additional LSA Protection. Retrieved February 13, 2015.
Связанные риски
Каталоги
Мы используем cookie-файлы, чтобы получить статистику, которая помогает нам улучшить сервис для вас с целью персонализации сервисов и предложений. Вы может прочитать подробнее о cookie-файлах или изменить настройки браузера. Продолжая пользоваться сайтом, вы даёте согласие на использование ваших cookie-файлов и соглашаетесь с Политикой обработки персональных данных.