How to Craft Effective Prompts for Threat Detection and Log Analysis

 

Introduction

As cybersecurity professionals, log analysis is one of our most powerful tools in the fight against threats. By sifting through the vast troves of data generated by our systems, we can uncover the telltale signs of malicious activity. But with so much information to process, where do we even begin?

The key is to arm ourselves with well-crafted prompts that guide our investigations and help us zero in on the threats that matter most. In this post, we’ll explore three sample prompts you can use to supercharge your threat detection and log analysis efforts. So grab your magnifying glass, and let’s dive in!

Prompt 1: Detecting Unusual Login Activity

One common indicator of potential compromise is unusual login activity. Attackers frequently attempt to brute force their way into accounts or use stolen credentials. To spot this, try a prompt like:

Show me all failed login attempts from IP addresses that have not previously authenticated successfully to this system within the past 30 days. Include the source IP, account name, and timestamp.

This will bubble up login attempts coming from new and unfamiliar locations, which could represent an attacker trying to gain a foothold. You can further refine this by looking for excessive failed attempts to a single account or many failed attempts across numerous accounts from the same IP.

Prompt 2: Identifying Suspicious Process Execution

Attackers will often attempt to run malicious tools or scripts after compromising a system. You can find evidence of this by analyzing process execution logs with a prompt such as:

Show me all processes launched from temporary directories or user profile AppData directories. Include the process name, associated username, full command line, and timestamp.

Legitimate programs rarely run from these locations, so this can quickly spotlight suspicious activity. Pay special attention to scripting engines like PowerShell or command line utilities like PsExec being launched from unusual paths. Examine the full command line to understand what the process was attempting to do.

Prompt 3: Spotting Anomalous Network Traffic

Compromised systems frequently communicate with external command and control (C2) servers to receive instructions or exfiltrate data. To detect this, try running the following prompt against network connection logs:

Show me all outbound network connections to IP addresses outside of our organization’s controlled address space. Exclude known good IPs like software update servers. Include source and destination IPs, destination port, connection duration, and total bytes transferred.

Look for long-duration connections or large data transfers to previously unseen IP addresses, especially on non-standard ports. Correlating this with the associated process can help determine if the traffic is malicious or benign.

Conclusion

Effective prompts like these are the key to unlocking the full potential of your log data for threat detection. You can quickly identify the needle in the haystack by thoughtfully constructing queries that target common attack behaviors.

But this is just the beginning. As you dig into your findings, let each answer guide you to the next question. Pivot from one data point to the next to paint a complete picture and scope the full extent of any potential compromise.

Mastering the art of prompt crafting takes practice, but the effort pays dividends. Over time, you’ll develop a robust library of questions that can be reused and adapted to fit evolving needs. So stay curious, keep honing your skills, and happy hunting!

More Help?

Ready to take your threat detection and log analysis skills to the next level? The experts at MicroSolved are here to help. With decades of experience on the front lines of cybersecurity, we can work with you to develop custom prompts tailored to your unique environment and risk profile. We’ll also show you how to integrate these prompts into a comprehensive threat-hunting program that proactively identifies and mitigates risks before they impact your business. Be sure to start asking the right questions before an attack succeeds. Contact us today at info@microsolved.com to schedule a consultation and build your defenses for tomorrow’s threats.

 

* AI tools were used as a research assistant for this content.

 

Let’s Talk About Audit Logs

CIS Control 8: Audit Log Management

Data is at the core of every business in today’s digital age. Protecting that data is of paramount importance. For this reason, the Center for Internet Security (CIS) developed the CIS Controls to provide a comprehensive framework for cybersecurity best practices.

One of these controls, CIS Control 8, focuses specifically on audit log management. This control aims to ensure that all events and security-related information are recorded and retained in an audit log for a defined period.

This article will explore the importance of audit log management as a fundamental component of any organization’s security posture. We will examine the CIS Control 8 safeguard requirements and industry-standard best practices for audit log management.

By following the procedures outlined in this article, organizations can improve their security posture, meet all CIS CSC version 8 safeguards, and ensure compliance with industry standards.

Why audit log management is essential

Audit log management is essential for every organization that wants to ensure its data security. The reason is simple: audit logs provide a comprehensive record of all events and security-related information that occurs within a system. This information is critical for incident response, threat detection, and compliance monitoring. Without audit logs, organizations would have no way of knowing who accessed what information, when or how the incident happened, or whether unauthorized users or suspicious activity occurred.

In addition to aiding in incident response and threat detection, audit log management also supports compliance with industry regulations and guidelines. Many compliance requirements mandate that organizations maintain a record of all activity that occurs on their systems. Failing to comply with these requirements can result in significant legal and financial penalties. Therefore, organizations prioritizing data security must take audit log management seriously and implement practices that meet their data security needs and safeguard requirements.

Best practices for audit log management

Audit log management is critical to an organization’s data security efforts. To ensure that your audit log management practices meet the CIS CSC version 8 guidelines and safeguard requirements, consider implementing the following best practices:

1. Define the audit log requirements: Assess the audit log requirements for your organization based on industry regulations, guidelines, and best practices. Define the data to be logged, audit events, and retention periods.

2. Establish audit policies and procedures: Develop audit policies and procedures that align with your organization’s requirements. Ensure these policies and procedures are implemented consistently across all systems and devices.

3. Secure audit logs: Audit logs should be collected, stored, and protected securely to prevent unauthorized access or tampering. Only authorized personnel should have access to audit logs.

4. Monitor and review audit logs: Regularly monitor and review audit logs for anomalies, suspicious activity, and security violations. This includes monitoring for unauthorized access attempts, changes to access rights, and software installations.

5. Configure audit logging settings: Ensure audit logs capture essential system information and user activity information. Configure audit logging settings to generate records of critical security controls, including attempts to gain unauthorized access or make unauthorized changes to the network.

6. Generate alerts: Configure the system to generate real-time alerts for critical events. This includes alerts for security violations, unauthorized access attempts, changes to access rights, and software installations.

7. Regularly test audit log management controls: Ensure audit log management controls are consistently implemented and reviewed. Conduct regular testing to ensure they are effective and meet your organization’s audit log requirements.

Organizations can establish a strong framework for incident response, threat detection, and compliance monitoring by implementing these best practices for audit log management. This will help safeguard against unauthorized access, malicious activity, and other security breaches, prevent legal and financial penalties, and maintain trust levels with clients and partners.

Audit log management policies

To establish audit log management policies that meet CIS CSC version 8 guidelines and safeguard requirements, organizations should follow the following sample policy:

1. Purpose: The purpose of this policy is to establish the principles for collecting, monitoring, and auditing all system and user activity logs to ensure compliance with industry regulations, guidelines, and best practices.

2. Scope: This policy applies to all employees, contractors, equipment, and facilities within the organization, including all workstations, servers, and network devices used in processing or storing sensitive or confidential information.

3. Policy:

– All computer systems and devices must generate audit logs that capture specified audit events, including user logins and accesses, system configuration changes, application accesses and modifications, and other system events necessary for detecting security violations, troubleshooting, and compliance monitoring.

– Audit logs must be generated in real-time and stored in a secure, centralized location that is inaccessible to unauthorized users.

– The retention period for audit logs must be at least 90 days, or longer if law or regulation requires.

– Only authorized personnel with appropriate access rights and clearances can view audit logs. Access to audit logs must be audited and reviewed regularly by the Information Security team.

– Audit logs must be reviewed regularly to identify patterns of suspicious activity, security violations, or potential security breaches. Any unauthorized access or security violation detected in the audit logs must be reported immediately to the Information Security team.

– Audit log management controls, and procedures must be tested periodically to ensure effectiveness and compliance with CIS CSC version 8 guidelines and safeguard requirements.

4. Enforcement: Failure to comply with this policy may result in disciplinary action, up to and including termination of employment or contract. All violations must be reported to the Information Security team immediately.

By implementing the above policy, organizations can ensure they meet the audit log management standards set forth by CIS CSC version 8 guidelines and safeguard requirements. This will help organizations prevent unauthorized access, malicious activity, and data breaches, maintain compliance with industry regulations, and protect the integrity and confidentiality of sensitive or confidential information.

Audit log management procedures

Here are the audit log management procedures that establish best practices for performing the work of this control:

I. Initial Setup

– Determine which audit events will be captured in the logs based on industry regulations, guidelines, and best practices.

– Configure all computer systems and devices to capture the specified audit events in the logs.

– Establish a secure, centralized location for storing the logs that is inaccessible to unauthorized users.

II. Ongoing Operations

– Set the logs to generate in real time.

– Monitor the logs regularly to detect security violations, troubleshoot, and monitor compliance.

– Ensure only authorized personnel with appropriate access rights can view the logs.

– Review the logs regularly to identify patterns of suspicious activity, security violations, or potential security breaches.

– Immediately report any unauthorized access or security violation detected in the logs to the Information Security team.

– Retain log data for at least 90 days, or longer if required by law or regulation.

III. Testing and Evaluation

– Test the audit log management controls and procedures periodically.

– Ensure that all testing and evaluation are conducted in compliance with CIS CSC version 8 guidelines and safeguard requirements.

By following these audit log management procedures, organizations can establish best practices for performing the work of this control and ensure that all system and user activities are properly monitored and audited. This will help organizations maintain compliance with industry regulations, prevent unauthorized access, and protect sensitive or confidential information from data breaches.

 

*This article was written with the help of AI tools and Grammarly.

Best Practices for DHCP Logging

As an IT and security auditor, I have seen the importance of DHCP logging in, ensuring network security, and troubleshooting network issues. Here are the best practices for DHCP logging that every organization should follow:

 

1. Enable DHCP Logging: DHCP logging should be turned on to record every event that occurs in the DHCP server. The logs should include information such as the time of the event, the IP address assigned, and the client’s MAC address.

2. Store DHCP Logs Securely: DHCP logs are sensitive information that should be stored in a secure location. Access to the logs should be restricted to authorized personnel only.

3. Use a Centralized Logging Solution: To manage DHCP logs, organizations should use a centralized logging solution that can handle logs from multiple DHCP servers. This makes monitoring logs, analyzing data, and detecting potential security threats easier.

4. Regularly Review DHCP Logs: Regularly reviewing DHCP logs can help detect and prevent unauthorized activities on the network. IT and security auditors should review logs to identify suspicious behavior, such as unauthorized IP and MAC addresses.

5. Analyze DHCP Logs for Network Performance Issues: DHCP logs can also help identify network performance issues. By reviewing logs, IT teams can identify IP address conflicts, subnet mask issues, and other network performance problems.

6. Monitor DHCP Lease Expiration: DHCP lease expiration is vital to ensure IP addresses are not allotted to unauthorized devices. DHCP logs can help to monitor lease expiration and to deactivate the leases of non-authorized devices.

7. Implement Alerting: IT and security audit teams should implement alerting options to ensure network security. By setting up alert mechanisms, they can be notified of suspicious activities such as unauthorized devices connecting to the network or DHCP problems.

8. Maintain DHCP Logs Retention Policy: An effective DHCP logs retention policy should be defined to ensure logs are saved for an appropriate period. This policy will help to provide historical audit trails and to comply with data protection laws.

 

Following these DHCP logging best practices will help ensure the network’s security and stability while simplifying the troubleshooting of any network issues.

Workstation Logging Best Practices

Why Workstation Logging Matters

Workstations are important components of any IT infrastructure, and they’re also one of the most overlooked. Often seen as expendable, many organizations fail to see the value of workstation logs, and how they can add to the visibility and detection capabilities of the security team. Workstations are quite likely to be early indicators of attack and malware infections. They are also often super useful in identifying manual attacker behaviors and performing adequate forensics.

Organizations that don’t maintain and organize workstation logs are usually missing out on some essential data and falling short of having across-the-enterprise visibility. This is especially true if you have a decentralized work environment. Simply enabling, configuring, and properly aggregating workstation logs can give you a huge forensic advantage. Adding real-time or near real-time log parsing and event alerting makes that advantage a superpower.

What to Log

The security events an organization captures on their workstations depend largely on industry-specific needs and relevant legal requirements. However, best practices call for several events that must be recorded and logged to ensure user accountability and to help organizations detect, understand, and recover from malicious events. These events include:

  • Authentication successes and failures for all users and services
  • Access control successes and failures for all users and services
  • Session activity, including files and applications used, especially system utilities and Powershell, if applicable
  • Changes in user access rights or privileges

The Bottom Line

Get busy logging on workstations. Make sure the logs are properly configured, aggregated, and processed as a part of your detection capabilities. Don’t view workstation logs as throw-aways. Instead, see them as a powerful lens for early detection, forensics, and attack recovery.

Update:

Thanks to @TheTokenFemale for pointing out that the logs should be sent somewhere off the system. I meant that by aggregation, but to clarify, the logs should be sent, processed, and archived using a log aggregation system or toolset that includes proper chain of evidence handling, alerting, and heuristics. It should also store and archive the relevant logs according to best practices and legal and regulatory guidance.