What to Look For in a DHCP Log Security Audit

Examining the DHCP logs

In today’s ever-evolving technology landscape, information security professionals face numerous challenges in ensuring the integrity and security of network infrastructures. As servers and devices communicate within networks, one crucial element to consider is DHCP (Dynamic Host Configuration Protocol) logs. These logs provide valuable insights into network activity, aiding in identifying security issues and potential threats. Examining DHCP logs through a thorough security audit is a critical step that can help organizations pinpoint vulnerabilities and effectively mitigate risks.

Why are DHCP Logs Important?

DHCP servers are central in assigning IP addresses and managing network resources. By constantly logging activities, DHCP servers enable administrators to track device connections, detect unauthorized access attempts, and identify abnormal network behavior. Consequently, DHCP logs clarify network utilization, application performance, and potential security incidents, making them a vital resource for information security professionals.

What Security Issues Can Be Identified in DHCP Logs?

When analyzing DHCP logs, security professionals should look for several key indicators of potential security concerns. These may include IP address conflicts, unauthorized IP address allocations, rogue DHCP servers, and abnormal DHCP server configurations. Additionally, DHCP logs can help uncover DoS (Denial of Service) attacks, attempts to bypass network access controls, and instances of network reconnaissance in some circumstances.

In conclusion, conducting a comprehensive security audit of DHCP logs is an essential practice for information security professionals. By leveraging the data contained within these logs, organizations can identify and respond to potential threats, ensuring the overall security and stability of their network infrastructure. Stay tuned for our upcoming blog posts, where we will delve deeper into the crucial aspects of DHCP log analysis and its role in fortifying network defenses.

Parsing the List of Events Logged

When conducting a DHCP log security audit, information security professionals must effectively parse the list of events logged to extract valuable insights and identify potential security issues.

To parse the logs and turn them into easily examined data, obtain the log files from the DHCP server. These log files are typically stored in a default logging path specified in the server parameters. Once acquired, the logs can be examined using various tools, including the server management console or event log viewer.

Begin by analyzing the log entries for critical events such as IP address conflicts, unauthorized IP address allocations, and abnormal DHCP server configurations. Look for any indications of rogue DHCP servers, as they can pose a significant security risk.

Furthermore, pay close attention to entries related to network reconnaissance, attempts to bypass network access controls and DoS attacks. These events can potentially reveal targeted attacks or malicious activities within the network.

By effectively parsing the list of events logged, information security professionals can uncover potential security issues, identify malicious activities, and take necessary measures to mitigate risks and protect the network infrastructure. It is crucial to remain vigilant and regularly conduct DHCP log audits to ensure the ongoing security of the network.

Heuristics that Represent Malicious Behaviors

When conducting a DHCP log security audit, information security professionals should look for specific heuristics representing potentially malicious behaviors. These heuristics can help identify security issues and prevent potential threats. It’s essential to understand what these heuristics mean and how to investigate them further.

Some examples of potentially malicious DHCP log events include:

1. Multiple DHCP Server Responses: This occurs when multiple devices on the network respond to DHCP requests, indicating the presence of rogue DHCP servers. Investigate the IP addresses associated with these responses to identify the unauthorized server and mitigate the security risk.

2. IP Address Pool Exhaustion: This event indicates that all available IP addresses in a subnet have been allocated or exhausted. It could suggest an unauthorized device or an unexpected influx of devices on the network. Investigate the cause and take appropriate actions to address the issue.

3. Unusual DHCP Lease Durations: DHCP lease durations outside the normal range can be suspicious. Short lease durations may indicate an attacker attempting to maintain control over an IP address. Long lease durations could suggest an attempt to evade IP address tracking. Investigate these events to identify any potential malicious activities.

Summary

A DHCP log security audit is crucial for information security professionals to detect and mitigate potential threats within their network. By analyzing DHCP log events, security teams can uncover malicious activities and take appropriate actions to protect their systems.

In this audit, several DHCP log events should be closely examined. One such event is multiple DHCP server responses, indicating the presence of rogue DHCP servers. Investigating the IP addresses associated with these responses can help identify unauthorized servers and address the security risk.

Another event that requires attention is IP address pool exhaustion. This event suggests the allocation of all available IP addresses in a subnet or an unexpected increase in devices on the network. Identifying the cause of this occurrence is vital to mitigate any potential security threats.

Unusual DHCP lease durations are also worth investigating. Short lease durations may suggest an attacker’s attempt to maintain control over an IP address, while long lease durations could indicate an effort to evade IP address tracking.

By conducting a thorough DHCP log security audit, security teams can proactively protect their networks from unauthorized devices, rogue servers, and potential malicious activities. Monitoring and analyzing DHCP log events should be an essential part of any organization’s overall security strategy.

* Just to let you know, we used some AI tools to gather the information for this article, and we polished it up with Grammarly to make sure it reads just right!

FAQ on Audit Log Best Practices

Q: What are audit logs?

A: Audit logs are records of all events and security-related information that occur within a system. This information is crucial for incident response, threat detection, and compliance monitoring.

Q: Why is audit log management important?

A: Audit log management is essential for every organization that wants to ensure its data security. 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. Moreover, audit log management supports compliance with industry regulations and guidelines.

Q: What are the best practices for audit log management?

A: 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 based on industry regulations, guidelines, and best practices.

2. Establish audit policies and procedures that align with your organization’s requirements and implement them consistently across all systems and devices.
3. Secure audit logs by collecting, storing, and protecting them securely to prevent unauthorized access or tampering.
4. Monitor and review audit logs regularly for anomalies, suspicious activity, and security violations, such as unauthorized access attempts, changes to access rights, and software installations.
5. 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 in real-time for critical events, including security violations, unauthorized access attempts, changes to access rights, and software installations.
7. Regularly test audit log management controls to ensure their effectiveness and meet your organization’s audit log requirements.

Q: What are the benefits of following audit log management best practices?

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

Q: How long should audit logs be kept?

A: As a general rule, storage of audit logs should include 90 days hot (meaning actively available for immediate review or alerting), 6 months warm (meaning they can be restored within hours), and two years cold (meaning they can be restored within days). However, organizations should define retention periods based on their audit log requirements and compliance regulations. [1] [2]

*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.

ClawBack from MicroSolved: A Solution for Detecting Data Exposures on IT Help Forums and Support Sites

Introduction

In today’s interconnected world, the sharing of information has become a necessary aspect of both personal and professional life. However, this also increases the risk of exposing sensitive data to malicious actors. IT help forums, and support sites are particularly vulnerable to such data exposures, as users inadvertently share information that can compromise their networks and systems. ClawBack from MicroSolved is a powerful tool designed to identify and mitigate these data exposures, helping organizations safeguard their sensitive information.

ClawBack: A Solution for Detecting Data Exposures

ClawBack is a data leakage detection tool developed by MicroSolved, an industry leader in information security services. It is specifically designed to scan the internet for sensitive data exposure, including IT help forums and support sites, where individuals and organizations may unwittingly disclose critical information. By utilizing cutting-edge search techniques, ClawBack can efficiently and effectively identify exposed data, enabling organizations to take appropriate action.

Key Features of ClawBack

  1. Advanced Search Algorithms: ClawBack employs sophisticated search algorithms to identify specific data types, such as personally identifiable information (PII), intellectual property, and system configuration details. This ensures that organizations can focus on addressing the most critical exposures.

  2. Comprehensive Coverage: ClawBack’s search capabilities extend beyond IT help forums and support sites. It also covers social media platforms, code repositories, and other online sources where sensitive data may be exposed.

  3. Customizable Searches: Organizations can tailor ClawBack’s search parameters to their unique needs, targeting specific keywords, internal project names, and even key/certificate shards. This customization ensures organizations can focus on the most relevant and potentially damaging exposures.

  4. Real-time Alerts: ClawBack provides real-time notifications to organizations when sensitive data is detected, allowing for prompt response and mitigation.

The Importance of Addressing Data Exposures

Organizations must recognize the importance of addressing data exposures proactively. The sensitive information disclosed on IT help forums and support sites can provide cybercriminals with the tools to infiltrate an organization’s network, steal valuable assets, and cause significant reputational damage.

ClawBack offers a proactive solution to this growing problem. Identifying and alerting organizations to potential data exposures allows them to take swift action to secure their sensitive information. This can include contacting the source of the exposure, requesting the removal of the exposed data, or initiating internal remediation processes to mitigate any potential risks.

Conclusion

In conclusion, ClawBack from MicroSolved is an invaluable tool for organizations seeking to protect their sensitive data from exposure on IT help forums and support sites. Its advanced search algorithms, comprehensive coverage, and real-time alerts enable organizations to proactively address data exposures and strengthen their security posture.

As cyber threats continue to evolve, it is essential for organizations to remain vigilant and invest in solutions like ClawBack to safeguard their valuable information. By doing so, organizations can build a robust security foundation that will help them thrive in the digital age.

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. 

3 Quick Thoughts for Small Utilities and Co-Ops

Recently I was asked to help some very small utilities and co-ops come up with some low cost/free ideas around detection. The group was very nice about explaining their issues, and here is a quick summary of some of the ideas we discussed.

1) Dump external router, firewall, AD and any remote access logs weekly to text and use simple parsers in python/perl or shell script to identify any high risk issues. Sure, this isn’t the same as having robust log monitoring tools (which none of these folks had), but even if you detect something really awful a week after it happens, you will still be ahead of the average curve of attackers having access for a month or more. You can build your scripts using some basis analytics, they will get better over time, and here are some ideas to get you started. You don’t need a lot of money to quickly handle dumped logs. Do the basics and improve.

2) Take advantage of cheap hardware, like the Raspberry Pi for easy to learn/use Linux boxes for scripting, log parsing or setting up cron jobs to automate tasks. For less than 50 bucks, you can have a powerful machine to do a lot of work for you and serve as a monitoring platform for a variety of tools. The group was all tied up in getting budget to buy server and workstation hardware – but had never taken the Pi seriously as a work platform. It’s mature enough to do a lot of non-mission critical (and some very important) work. It’s fantastic if you’re looking for a quick and dirty way to gain some Linux capabilities in confined Windows world.

3) One of the best bang for the buck services we have at MSI is device configuration reviews. For significantly less money than a penetration test, we can review your external routers, firewall and VPN for configuration issues, improper rules/ACLs and insecure settings. If you combine this with an exercise like attack surface mapping and threat modeling, you can get a significant amount of insight without resorting to (and paying for) vulnerability assessments and penetration testing. Sure, the data might not be as granular, and we still have to do some level of port scanning and service ID, but we have a variety of safe ways to do that work – and you get some great information. You can then make risk-based decisions about the data and decide what you want to act on and pay attention to. If your budget is tight – get in touch and discuss this approach with us.

I love to talk with utilities and especially smaller organizations that want to do the right thing, but might face budget constraints. If they’re willing to have an open, honest conversation, I am more than willing to get creative and engage to help them solve problems within their needs. We’d rather get creative and solve an issue to protect the infrastructure than have them get compromised by threat actors looking to do harm.

If you want to discuss this or any security or risk management issue, get in touch here.  

Detecting Info Leaks with ClawBack

Clawback smallClawBack Is Purpose Built to Detect Info Leaks

ClawBack is MicroSolved’s cloud-based SaaS solution for performing info leak detection. We built the tool because we worked so many incidents and breaches related to three common types of info leaks:

  • Leaked Credentials – this is so common that it lies at the root of thousands of incidents over the last several years, attackers harvest stolen and leaked logins and passwords and use them anywhere they think they can gain access – this is so common, it is even categorized by OWASP as a specific form of attack: credential stuffing 
  • Leaked Configurations – attackers love to comb through leaked device and application configuration files for credentials, of course, but also for details about the network or app environment, sensitive data locations, cryptographic secrets and network management information they can use to gain control or access
  • Leaked Code – leaked source code is a huge boon for attackers; often leaking sensitive intellectual property that they can sell on the dark web to your competitors or parse for vulnerabilities in your environment or products

MicroSolved knows how damaging these info leaks can be to organizations, no matter the type. That’s exactly why we built ClawBack to provide ongoing monitoring for the info leak terms that matter most to you.

How to Get Started Detecting Info Leaks

Putting ClawBack to work for you is incredibly easy. Most customers are up and monitoring for info leaks within 5 minutes.

There is no hardware, software, appliance or agent to deploy. The browser-based interface is simple to use, yet flexible enough to meet the challenges of the modern web. 

First, get a feel for some terms that you would like to monitor that are unique to your organization. Good examples might be unique user names, application names, server names, internal code libraries, IP address ranges, SNMP community strings, the first few hex characters of certificates or encryption keys, etc. Anything that is unique to your organization or at the very least, uncommon. 

Next, register for a ClawBack account by clicking here.

Once your account is created, and you follow the steps to validate it, you can login to the ClawBack application. Here, you will be able to choose the level of subscription that you would like, picking from the three different service levels available. You will also be able to input your payment information and set up additional team members to use the application, if available at your subscription level. 

Next, click on Monitoring Terms and input the terms that you identified in the first step. ClawBack will immediately go and search for any info leaks related to your terms as you put them in. Additionally, ClawBack will continually monitor for the terms going forward and provide alerts for any info leaks that appear in the common locations around the web. 

How To View Any Info Leaks

Reviewing any info leaks found is easy, as well. Simply click on Alerts on the top menu. Here, your alerts will be displayed, in a sortable list. The list contains a summary of each identified leak, the term it matched and the location of the leak. You can click on the alert to view the identified page. Once reviewed, you can archive the alert, where it will remain in the system and is visible in your archive, or you can mark it as a false positive, and it will be removed from your dataset but ClawBack will remember the leak and won’t alert you again for that specific URL. 

If you have access to the export function, based on your subscription level, you can also so export alerts to a CSV file for uploading into SIEM/SOAR tools or ticketing systems. It’s that easy! 

You can find a more specific walkthrough for finding code leaks here, along with some screen shots of the product in action.

You can learn more about ClawBack and view some use case videos and demo videos at the ClawBack homepage.

Give ClawBack a try today and you can put your worries to rest that unknown info leaks might be out there doing damage to your organization. It’s so easy, so affordable and so powerful that it makes worries about info leaks obsolete.

Introducing ClawBack :: Data Leak Detection Powered By MicroSolved

Cb 10We’ve worked with our clients and partners to put together a world-class data leak detection platform that is so easy to use that most security teams have it up and running in less than five minutes. No hardware appliance or software agent to deploy, no console to manage and, best of all, affordable for organizations of any size.

In short, ClawBack is data leak detection done right.

There’s a lot more to the story, and that’s why we put together this short (3 minute) video to describe ClawBack, its capabilities and why we created it. Once you check it out, we think you’ll see just how ClawBack fits the mission of MSI to make the online world safer for all of us.

View the video here.

You can also learn a lot more about ClawBack, its use cases and some of the ways we hope it can help you here. On that page, you can also find pricing for three different levels of service, more videos walking you through how to sign up and a video demo of the platform.

Lastly, if you’d like to just get started, you can visit the ClawBack Portal, and select Register to sign up and put ClawBack to work immediately on providing detection for your leaked data.

In the coming weeks, we’ll be talking more about what drove us to develop ClawBack, the success stories we’ve had just while building and testing the platform, and provide some more specifics about how to make the most of ClawBack’s capabilities. In the meantime, thanks for reading, check it out and if you have any questions, drop us a line.

Revisiting Nuance Detection

The core of nuance detection is to extend alerting capabilities into finding situations that specifically should not exist, and if they happen, would indicate a significant security failure. A simple, elegant example would be a motion sensor on a safe in your home, combined with something like your home alarm system.
 
A significant failure state would be for the motion sensor inside the safe to trigger while the home alarm system is set in away mode. When the alarm is in away mode, there should be no condition that triggers motion inside the safe. If motion is detected, anytime, you might choose to alert in a minor way. But, if the alarm is set to away mode, you might signal all kinds of calamity and flashing lights, bells and whistles, for example.
 
This same approach can apply to your network environment, applications or data systems. Define what a significant failure state looks like, and then create detection and alerting mechanisms, even if conditional, for the indicators of that state. It can be easy. 
 
I remember thinking more deeply about this for the first time when I saw Marcus Ranum give his network burglar alarm speech at Defcon, what seems like a 1000 years ago now. That moment changed my life forever. Since then, I have always wanted to work on small detections. The most nuanced of fail states. The deepest signs of compromise. HoneyPoint™ came from that line of thinking, albeit, many years later. (Thanks, Marcus, you are amazing! BTW.) 🙂
 
I’ve written about approaches to it in the past, too. Things like detecting web shells, detection in depth techniques and such. I even made some nice maturity and deployment models.
 
This month, I will be revisiting nuance detection more deeply. Creating some more content around it, and speaking about it more openly. I’ll also cover how we have extended HoneyPoint with the Handler portion of HoneyPoint Agent. in order to fully support event management and data handling into your security alerting systems from basic scripts and simple tools you can create yourself. 
 
Stay tuned, and in the meantime, drop me a line on Twitter (@lbhuston) and let me know more about nuance detections you can think of or have implemented. I’d love to hear more about it.