Mitigations

Making these files immutable and only changeable by certain administrators will limit the ability for adversaries to easily create user level persistence.

Access Management technologies can be used to enforce authorization polices and decisions, especially when existing field devices do not provide sufficient capabilities to support user identification and authentication. [1] These technologies typically utilize an in-line network device or gateway system to prevent access to unauthenticated users, while also integrating with an authentication service to first verify user credentials. [2]

Access tokens are an integral part of the security system within Windows and cannot be turned off. However, an attacker must already have administrator level access on the local system to make full use of this technique; be sure to restrict users and accounts to the least privileges they require to do their job.

Any user can also spoof access tokens if they have legitimate credentials. Follow mitigation guidelines for preventing adversary use of Valid Accounts. Limit permissions so that users and user groups cannot create tokens. This setting should be defined for the local system account only. GPO: Computer Configuration > [Policies] > Windows Settings > Security Settings > Local Policies > User Rights Assignment: Create a token object. [1] Also define who can create a process level token to only the local and network service through GPO: Computer Configuration > [Policies] > Windows Settings > Security Settings > Local Policies > User Rights Assignment: Replace a process level token. [2]

Also limit opportunities for adversaries to increase privileges by limiting Privilege Escalation opportunities.

To use this technique remotely, an adversary must use it in conjunction with RDP. Ensure that Network Level Authentication is enabled to force the remote desktop session to authenticate before the session is created and the login screen displayed. It is enabled by default on Windows Vista and later. [1]

If possible, use a Remote Desktop Gateway to manage connections and security configuration of RDP within a network. [2]

Identify and block potentially malicious software that may be executed by an adversary with this technique by using whitelisting [3] tools, like AppLocker, [4] [5] or Software Restriction Policies [6] where appropriate. [7]

Prevent administrator accounts from being enumerated when an application is elevating through UAC since it can lead to the disclosure of account names. The Registry key is located HKLM\ SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\CredUI\EnumerateAdministrators. It can be disabled through GPO: Computer Configuration > [Policies] > Administrative Templates > Windows Components > Credential User Interface: E numerate administrator accounts on elevation. [1]

Identify unnecessary system utilities or potentially malicious software that may be used to acquire information about system and domain accounts, and audit and/or block them by using whitelisting [2] tools, like AppLocker, [3] [4] or Software Restriction Policies [5] where appropriate. [6]

Account Use Policies help mitigate unauthorized access by configuring and enforcing rules that govern how and when accounts can be used. These policies include enforcing account lockout mechanisms, restricting login times, and setting inactivity timeouts. Proper configuration of these policies reduces the risk of brute-force attacks, credential theft, and unauthorized access by limiting the opportunities for malicious actors to exploit accounts. This mitigation can be implemented through the following measures:

Account Lockout Policies:

- Implementation: Configure account lockout settings so that after a defined number of failed login attempts (e.g., 3-5 attempts), the account is locked for a specific time period (e.g., 15 minutes) or requires an administrator to unlock it. - Use Case: This prevents brute-force attacks by limiting how many incorrect password attempts can be made before the account is temporarily disabled, reducing the likelihood of an attacker successfully guessing a password.

Login Time Restrictions:

- Implementation: Set up login time policies to restrict when users or groups can log into systems. For example, only allowing login during standard business hours (e.g., 8 AM to 6 PM) for non-administrative accounts. - Use Case: This prevents unauthorized access outside of approved working hours, where login attempts might be more suspicious or harder to monitor. For example, if an account that is only supposed to be active during the day logs in at 2 AM, it should raise an alert or be blocked.

Inactivity Timeout and Session Termination:

- Implementation: Enforce session timeouts after a period of inactivity (e.g., 10-15 minutes) and require users to re-authenticate if they wish to resume the session. - Use Case: This policy prevents attackers from hijacking active sessions left unattended. For example, if an employee walks away from their computer without locking it, an attacker with physical access to the system would be unable to exploit the session.

Password Aging Policies:

- Implementation: Enforce password aging rules, requiring users to change their passwords after a defined period (e.g., 90 days) and ensure passwords are not reused by maintaining a password history. - Use Case: This limits the risk of compromised passwords being used indefinitely. Regular password changes make it more difficult for attackers to reuse stolen credentials.

Account Expiration and Deactivation:

- Implementation: Configure user accounts, especially for temporary or contract workers, to automatically expire after a set date or event. Accounts that remain unused for a specific period should be deactivated automatically. - Use Case: This prevents dormant accounts from becoming an attack vector. For example, an attacker can exploit unused accounts if they are not properly monitored or deactivated.

**Tools for Implementation**:

- Group Policy Objects (GPOs) in Windows: To enforce account lockout thresholds, login time restrictions, session timeouts, and password policies. - Identity and Access Management (IAM) solutions: For centralized management of user accounts, session policies, and automated deactivation of accounts. - Security Information and Event Management (SIEM) platforms: To monitor and alert on unusual login activity, such as failed logins or out-of-hours access attempts. - Multi-Factor Authentication (MFA) Tools: To further enforce secure login attempts, preventing brute-force or credential stuffing attacks.

Configure features related to account use like login attempt lockouts, specific login times, etc.

Implement robust Active Directory (AD) configurations using group policies to secure user accounts, control access, and minimize the attack surface. AD configurations enable centralized control over account settings, logon policies, and permissions, reducing the risk of unauthorized access and lateral movement within the network. This mitigation can be implemented through the following measures:

Account Configuration:

- Implementation: Use domain accounts instead of local accounts to leverage AD’s centralized management, including group policies, auditing, and access control. - Use Case: For IT staff managing shared resources, provision domain accounts that allow IT teams to log in centrally, reducing the risk of unmanaged, rogue local accounts on individual machines.

Interactive Logon Restrictions:

- Implementation: Configure group policies to restrict interactive logons (e.g., direct physical or RDP logons) for service accounts or privileged accounts that do not require such access. - Use Case: Prevent service accounts, such as SQL Server accounts, from having interactive logon privileges. This reduces the risk of these accounts being leveraged for lateral movement if compromised.

Remote Desktop Settings:

- Implementation: Limit Remote Desktop Protocol (RDP) access to specific, authorized accounts. Use group policies to enforce this, allowing only necessary users to establish RDP sessions. - Use Case: On sensitive servers (e.g., domain controllers or financial databases), restrict RDP access to administrative accounts only, while all other users are denied access.

Dedicated Administrative Accounts:

- Implementation: Create domain-wide administrative accounts that are restricted from interactive logons, designed solely for high-level tasks (e.g., software installation, patching). - Use Case: Create separate administrative accounts for different purposes, such as one set of accounts for installations and another for managing repository access. This limits exposure and helps reduce attack vectors.

Authentication Silos:

- Implementation: Configure Authentication Silos in AD, using group policies to create access zones with restrictions based on membership, such as the Protected Users security group. This restricts access to critical accounts and minimizes exposure to potential threats. - Use Case: Place high-risk or high-value accounts, such as executive or administrative accounts, in an Authentication Silo with extra controls, limiting their exposure to only necessary systems. This reduces the risk of credential misuse or abuse if these accounts are compromised.

**Tools for Implementation**:

- Active Directory Group Policies: Use Group Policy Management Console (GPMC) to configure, deploy, and enforce policies across AD environments. - PowerShell: Automate account configuration, logon restrictions, and policy application using PowerShell scripts. - AD Administrative Center: Manage Authentication Silos and configure high-level policies for critical user groups within AD.

Configure Active Directory to prevent use of certain techniques; use security identifier (SID) Filtering, etc.

Antivirus/Antimalware solutions utilize signatures, heuristics, and behavioral analysis to detect, block, and remediate malicious software, including viruses, trojans, ransomware, and spyware. These solutions continuously monitor endpoints and systems for known malicious patterns and suspicious behaviors that indicate compromise. Antivirus/Antimalware software should be deployed across all devices, with automated updates to ensure protection against the latest threats. This mitigation can be implemented through the following measures:

Signature-Based Detection:

- Implementation: Use predefined signatures to identify known malware based on unique patterns such as file hashes, byte sequences, or command-line arguments. This method is effective against known threats. - Use Case: When malware like "Emotet" is detected, its signature (such as a specific file hash) matches a known database of malicious software, triggering an alert and allowing immediate quarantine of the infected file.

Heuristic-Based Detection:

- Implementation: Deploy heuristic algorithms that analyze behavior and characteristics of files and processes to identify potential malware, even if it doesn’t match a known signature. - Use Case: If a program attempts to modify multiple critical system files or initiate suspicious network communications, heuristic analysis may flag it as potentially malicious, even if no specific malware signature is available.

Behavioral Detection (Behavior Prevention):

- Implementation: Use behavioral analysis to detect patterns of abnormal activities, such as unusual system calls, unauthorized file encryption, or attempts to escalate privileges. - Use Case: Behavioral analysis can detect ransomware attacks early by identifying behavior like mass file encryption, even before a specific ransomware signature has been identified.

Real-Time Scanning:

- Implementation: Enable real-time scanning to automatically inspect files and network traffic for signs of malware as they are accessed, downloaded, or executed. - Use Case: When a user downloads an email attachment, the antivirus solution scans the file in real-time, checking it against both signatures and heuristics to detect any malicious content before it can be opened.

Cloud-Assisted Threat Intelligence:

- Implementation: Use cloud-based threat intelligence to ensure the antivirus solution can access the latest malware definitions and real-time threat feeds from a global database of emerging threats. - Use Case: Cloud-assisted antivirus solutions quickly identify newly discovered malware by cross-referencing against global threat databases, providing real-time protection against zero-day attacks.

**Tools for Implementation**:

- Endpoint Security Platforms: Use solutions such as EDR for comprehensive antivirus/antimalware protection across all systems. - Centralized Management: Implement centralized antivirus management consoles that provide visibility into threat activity, enable policy enforcement, and automate updates. - Behavioral Analysis Tools: Leverage solutions with advanced behavioral analysis capabilities to detect malicious activity patterns that don’t rely on known signatures.

Mobile security products, such as Mobile Threat Defense (MTD), offer various device-based mitigations against certain behaviors.

Use signatures or heuristics to detect malicious software. Within industrial control environments, antivirus/antimalware installations should be limited to assets that are not involved in critical or real-time operations. To minimize the impact to system availability, all products should first be validated within a representative test environment before deployment to production systems. [1]

Identify and block potentially malicious software that may be executed through AppCert DLLs by using whitelisting [1] tools, like AppLocker, [2] [3] that are capable of auditing and/or blocking unknown DLLs.

Upgrade to Windows 8 or later and enable secure boot.

Identify and block potentially malicious software that may be executed through AppInit DLLs by using whitelisting [1] tools, like AppLocker, [2] [3] that are capable of auditing and/or blocking unknown DLLs.

Require that all AppleScript be signed by a trusted developer ID before being executed - this will prevent random AppleScript code from executing [1]. This subjects AppleScript code to the same scrutiny as other .app files passing through Gatekeeper.

Grant access to application deployment systems only to a limited number of authorized administrators. Ensure proper system and access isolation for critical network systems through use of firewalls, account privilege separation, group policy, and multifactor authentication. Verify that account credentials that may be used to access deployment systems are unique and not used throughout the enterprise network. Patch deployment systems regularly to prevent potential remote access through Exploitation for Privilege Escalation.

If the application deployment system can be configured to deploy only signed binaries, then ensure that the trusted signing certificates are not co-located with the application deployment system and are instead located on a system that cannot be accessed remotely or to which remote access is tightly controlled.

Application Developer Guidance focuses on providing developers with the knowledge, tools, and best practices needed to write secure code, reduce vulnerabilities, and implement secure design principles. By integrating security throughout the software development lifecycle (SDLC), this mitigation aims to prevent the introduction of exploitable weaknesses in applications, systems, and APIs. This mitigation can be implemented through the following measures: Preventing SQL Injection (Secure Coding Practice):

- Implementation: Train developers to use parameterized queries or prepared statements instead of directly embedding user input into SQL queries. - Use Case: A web application accepts user input to search a database. By sanitizing and validating user inputs, developers can prevent attackers from injecting malicious SQL commands.

Cross-Site Scripting (XSS) Mitigation:

- Implementation: Require developers to implement output encoding for all user-generated content displayed on a web page. - Use Case: An e-commerce site allows users to leave product reviews. Properly encoding and escaping user inputs prevents malicious scripts from being executed in other users’ browsers.

Secure API Design:

- Implementation: Train developers to authenticate all API endpoints and avoid exposing sensitive information in API responses. - Use Case: A mobile banking application uses APIs for account management. By enforcing token-based authentication for every API call, developers reduce the risk of unauthorized access.

Static Code Analysis in the Build Pipeline:

- Implementation: Incorporate tools into CI/CD pipelines to automatically scan for vulnerabilities during the build process. - Use Case: A fintech company integrates static analysis tools to detect hardcoded credentials in their source code before deployment.

Threat Modeling in the Design Phase:

- Implementation: Use frameworks like STRIDE (Spoofing, Tampering, Repudiation, Information Disclosure, Denial of Service, Elevation of Privilege) to assess threats during application design. - Use Case: Before launching a customer portal, a SaaS company identifies potential abuse cases, such as session hijacking, and designs mitigations like secure session management.

**Tools for Implementation**:

- Static Code Analysis Tools: Use tools that can scan for known vulnerabilities in source code. - Dynamic Application Security Testing (DAST): Use tools like Burp Suite or OWASP ZAP to simulate runtime attacks and identify vulnerabilities. - Secure Frameworks: Recommend secure-by-default frameworks (e.g., Django for Python, Spring Security for Java) that enforce security best practices.

Application Developer Guidance focuses on providing developers with the knowledge, tools, and best practices needed to write secure code, reduce vulnerabilities, and implement secure design principles. By integrating security throughout the software development lifecycle (SDLC), this mitigation aims to prevent the introduction of exploitable weaknesses in applications, systems, and APIs. This mitigation can be implemented through the following measures: Preventing SQL Injection (Secure Coding Practice):

- Implementation: Train developers to use parameterized queries or prepared statements instead of directly embedding user input into SQL queries. - Use Case: A web application accepts user input to search a database. By sanitizing and validating user inputs, developers can prevent attackers from injecting malicious SQL commands.

Cross-Site Scripting (XSS) Mitigation:

- Implementation: Require developers to implement output encoding for all user-generated content displayed on a web page. - Use Case: An e-commerce site allows users to leave product reviews. Properly encoding and escaping user inputs prevents malicious scripts from being executed in other users’ browsers.

Secure API Design:

- Implementation: Train developers to authenticate all API endpoints and avoid exposing sensitive information in API responses. - Use Case: A mobile banking application uses APIs for account management. By enforcing token-based authentication for every API call, developers reduce the risk of unauthorized access.

Static Code Analysis in the Build Pipeline:

- Implementation: Incorporate tools into CI/CD pipelines to automatically scan for vulnerabilities during the build process. - Use Case: A fintech company integrates static analysis tools to detect hardcoded credentials in their source code before deployment.

Threat Modeling in the Design Phase:

- Implementation: Use frameworks like STRIDE (Spoofing, Tampering, Repudiation, Information Disclosure, Denial of Service, Elevation of Privilege) to assess threats during application design. - Use Case: Before launching a customer portal, a SaaS company identifies potential abuse cases, such as session hijacking, and designs mitigations like secure session management.

**Tools for Implementation**:

- Static Code Analysis Tools: Use tools that can scan for known vulnerabilities in source code. - Dynamic Application Security Testing (DAST): Use tools like Burp Suite or OWASP ZAP to simulate runtime attacks and identify vulnerabilities. - Secure Frameworks: Recommend secure-by-default frameworks (e.g., Django for Python, Spring Security for Java) that enforce security best practices.

This mitigation describes any guidance or training given to developers of applications to avoid introducing security weaknesses that an adversary may be able to take advantage of.

Application Isolation and Sandboxing refers to the technique of restricting the execution of code to a controlled and isolated environment (e.g., a virtual environment, container, or sandbox). This method prevents potentially malicious code from affecting the rest of the system or network by limiting access to sensitive resources and critical operations. The goal is to contain threats and minimize their impact. This mitigation can be implemented through the following measures:

Browser Sandboxing:

- Use Case: Implement browser sandboxing to isolate untrusted web content and prevent malicious web pages or scripts from accessing sensitive system resources or initiating unauthorized downloads. - Implementation: Use browsers with built-in sandboxing features (e.g., Google Chrome, Microsoft Edge) or deploy enhanced browser security frameworks that limit the execution scope of active content. Consider controls that monitor or restrict script-based file generation and downloads commonly abused in evasion techniques like HTML smuggling.

Application Virtualization:

- Use Case: Deploy critical or high-risk applications in a virtualized environment to ensure any compromise does not affect the host system. - Implementation: Use application virtualization platforms to run applications in isolated environments.

Email Attachment Sandboxing:

- Use Case: Route email attachments to a sandbox environment to detect and block malware before delivering emails to end-users. - Implementation: Integrate security solutions with sandbox capabilities to analyze email attachments.

Endpoint Sandboxing:

- Use Case: Run all downloaded files and applications in a restricted environment to monitor their behavior for malicious activity. - Implementation: Use endpoint protection tools for sandboxing at the endpoint level.

Restrict the execution of code to a virtual environment on or in-transit to an endpoint system.

There currently aren't a lot of ways to mitigate application shimming. Disabling the Shim Engine isn't recommended because Windows depends on shimming for interoperability and software may become unstable or not work. Microsoft released an optional patch update - KB3045645 - that will remove the "auto-elevate" flag within the sdbinst.exe. This will prevent use of application shimming to bypass UAC.

Changing UAC settings to "Always Notify" will give the user more visibility when UAC elevation is requested, however, this option will not be popular among users due to the constant UAC interruptions.

Enterprises can vet applications for exploitable vulnerabilities or unwanted (privacy-invasive or malicious) behaviors. Enterprises can inspect applications themselves or use a third-party service.

Enterprises may impose policies to only allow pre-approved applications to be installed on their devices or may impose policies to block use of specific applications known to have issues. In Bring Your Own Device (BYOD) environments, enterprises may only be able to impose these policies over an enterprise-managed portion of the device.

Application Vetting is not a complete mitigation. Techniques such as Evade Analysis Environment exist that can enable adversaries to bypass vetting.

Identify unnecessary system utilities or potentially malicious software that may be used to acquire information, and audit and/or block them by using whitelisting [1] tools, like AppLocker, [2] [3] or Software Restriction Policies [4] where appropriate. [5]

Enable remote attestation capabilities when available (such as Android SafetyNet or Samsung Knox TIMA Attestation) and prohibit devices that fail the attestation from accessing enterprise resources.