I can remember it like it was yesterday...  Casey, Hans, Jason, Scott, Sam, Bill and I were slowly destroying my hotel suite at Circle City Con while trying to win the 2015 CTF. (We took 2nd place and never got our GoPro prize... still sour, can you tell?)  Amongst all the teams’ brilliant ideas that evening, was that we really needed a blog. A few hours later, #_shellntel was born.

Our intent was (and still is) to focus on pentesting, hacking and offensive security; we feared that some articles may be too edgy for some corporate/professional readers. Therefore, we separated our #_shellntel articles from other SynerComm blogs. Over the past 7 years, things have changed and today everyone loves pentester articles.

We are grateful for the loyal support of our #_shellntel readers throughout the years. Please continue to read about the latest IT news, tech trends, and cybersecurity threats on our new blog at www.synercomm.com/blog or link directly to our #_shellntel articles at www.synercomm.com/blog/tag/shellntel/. All of our existing content was moved, and all new articles will be published here going forward.

Thank you always,

Brian Judd, VP Information Assurance

SynerComm, Inc.

Whether doing security research or troubleshooting networks, network sniffers and packet analysis can be invaluable tools. If you're a network engineer like me, you've probably been holding onto your favorite 4 or 8-port 10/100 hub for 25 years now. The reason is that hubs (not switches) make great network taps. By design, all Ethernet transmissions on a hub are sent to all ports. To monitor another device, you can place it on a hub along with your laptop/sniffer and then connect that hub to the rest of your network (if needed). All packets sent to or from this device will also be sent to your sniffer on the hub. Even 25 years later, the hub I bought during college still makes a great network tap. It was only recently that I needed something a little more powerful.

Hubs date back to the early years of Ethernet when twisted-pair cabling started being used for networking (like Cat-3/Cat-5). These networks initially ran at only 10 Mb/s and early hubs were also limited to that throughput. As technology advanced, Ethernet speeds increased to 100 Mb/s and new Ethernet switches were created. Unlike hubs, switches only forward packets to the port needed for the packet to reach its intended destination. This was done because hubs can suffer from "collisions" that occur when more than one device tries to transmit at the same time. Switches eliminate packet collisions and allow networks to remain efficient as the number of networked devices grow. Modern switches also support 10/100 Mbit/s and gigabit (1,000 Mbit/s) throughputs. While this is great for network performance, most inexpensive switches can't be used as a network tap.

So, what can you do when you need to monitor a highspeed gigabit link and can't afford an expensive network tap? How about the $39.99 10/100/1000 8-port Netgear GS308E switch with "Enhanced Features". As you probably guessed, one of those enhanced features, called Port Mirroring, allows this switch to be used as a network tap. And unlike a hub, port mirroring allows you to monitor another port without it also monitoring you.

How To:

Follow the instructions below to configure a high-speed (up to gigabit) network tap using the Netgear GS308E switch.

Physical connections:

Port 1 – Device (or Network Segment) Being Monitored

Port 2 – Sniffer (My Laptop)

Port 8 – Uplink to Network (optional)

  1. Log into your Netgear GS308E by going to it's management IP address with a web browser. The default URL is if there is no DHCP server available to assign an address. (See owners manual if you are having trouble accessing the switch management.)
  2. Click: System (top row) >> Monitoring (2nd row) >> Monitoring (left button)
  3. Port Mirroring Configuration:
    1. Click the Source Port of the port you want to monitor. In our example, this is Port 1. Multiple ports can be selected if you want to monitor several ports at the same time.
    2. In the Mirroring dropdown, select Enable.
    3. In the Destination Port dropdown, select the port that you will connect your sniffer to. In our example, this is Port 2.
    4. Validate that your settings are correct and click Apply.

A screenshot of a computer Description automatically generated.

That's all there is to it! Make sure your devices are connected to the proper ports and start your network analysis.

Warning: This blog contains purposeful marketing and gratuitous plugs for SynerComm’s CASM™ Subscription services. Seriously though, the following article will present the need for better external visibility and vulnerability management.

Whether you are vulnerability scanning to meet compliance requirements or doing it as part of good security practices, there is a universal need. At the time of this article, there are essentially three equally capable and qualified scanning solutions. They include products from Tenable, Rapid7 and Qualys. My point is that each of these scanning solutions, if configured correctly, should produce accurate and similar results. Therefore, as long as your scanning provider is using one of these three solutions, they should be able to detect vulnerabilities. SynerComm starts with a top scanner and then addresses all the gaps that your MSSP is missing. 

Vulnerability scanning and analysis is a critical process within all information security programs. Scanners should find missing patches, dangerous configurations, default passwords, and hundreds of other weaknesses. Their technology is based on probing systems over networks and trying to determine if the system exhibits specific vulnerabilities. While the process itself isn’t complicated, many organizations choose to outsource it to a managed service provider. If you need a provider or already have one, it’s time to upgrade to Continuous Attack Surface Management (CASM™). 

Ditch your Vulnerability Scanning MSSP

Vulnerability scanning MSSPs served their role well for many years but failed to keep up. They failed to keep with cloud migrations, failed to keep up with the rate of IT changes, and failed to provide tools that simplify and enable security for their subscribers. 

VS-MSSPs Lack Discovery of New Assets

VS-MSSPs are Plagued with False Positives and Fail to Accurately Describe Risk 

VS-MSSPs Lack Security Expertise

The benefits of Continuous Attack Surface Management include:

If you’ve ever wondered what your systems and exposures look like to a cyber-criminal, just ask a pentester. SynerComm’s CASM® Engine was originally designed to provide accurate and timely reconnaissance information to our penetration testers. Access to this data and our ‘Findings-Based Reporting’ is available to all CASM® and Continuous Penetration Test subscribers. 

Learn more about our Continuous Attack Surface Management, SynerComm’s CASM® Engine, and our industry-leading Continuous Penetration Test subscriptions. 

Scheduled Scanning of Known Assets✔️✔️
Ad-Hoc (Manual) Scanning✔️✔️
24/7 Online Dashboard Reporting✔️✔️
Discovery of New Assets✔️
Elimination of False-Positives✔️
Validated Findings✔️
Risk-Based Customizable Alerts✔️
Access to Penetration Testers✔️


In penetration testing, it’s important to have an accurate scope and even more important to stick to it. This can be simple when the scope is limited to a company’s internet service provider (ISP) or ARIN provided IP ranges. But in many cases, our client’s public systems have grown to include multiple cloud hosted servers, applications, and services. It may seem obvious to say that anything owned or managed by the company should be in-scope for testing, but how do we know what is “owned or managed”? Ideally, we’d test everything that creates risk to an organization, but that isn’t always possible… read on.

I led this article by stating that an accurate scope is critical to penetration testing. If the scope only includes the IP blocks provided by your ISP, you’re probably missing systems that should be tested. Alternately, pentesting a system that you don’t have permission to test could land you in hot water. The good news is that hosting providers like Amazon Web Services (AWS) and Azure allow penetration testing of systems within your account. In other words, because you manage them, you have the right to pentest them. In these environments, pentesting your individual servers (or services) does not affect “neighboring” systems or the cloud host’s infrastructure.

In addition to the many compute and storage providers, you may also have websites and applications that are hosted and managed by a 3rd party. These still create risk to your company, but the hosting provider has complete control over who has permission to perform testing. When there is custom code or sensitive data at play, you should be seeking (written) permission to pentest/assess these systems and applications. If the host is unable or unwilling to allow testing, they should provide evidence of their own independent testing.

There are also going to be cloud systems that, despite creating risk to your organization, can’t be tested at all. This includes software as a service (SaaS) applications like SalesForce, SAP,  and DocuSign. 

And you guessed it… there are also systems like Azure AD, Microsoft 365, and CloudFlare that are not explicitly in-scope, but their controls may not be avoidable during external pentests. MS 365 uses Azure AD which is basically a public extension of your on-premise (internal) Active Directory; complete with extremely high-performance authentication services. Most authentication attacks today take place directly against Azure AD due to its performance and public accessibility. In other words, an attacker could have your passwords before they ever touch a system on your network. Likewise, if your company uses CloudFlare to protect your websites and web applications, it inherently becomes part of the scope because testing of these apps should force you through their proxy/control.

Hopefully this information will help you plan for your next pentest or assessment. If your company maintains an accurate inventory of external systems that includes all of your data center and cloud systems, you’re already off to a great start. Still, there is always value in doing regular searches and discoveries for systems you may be missing. One method involves reviewing your external DNS to obtain a list of A and CNAME records for your domains.  (For ALL of your domains…)  By resolving all of your domains and subdomains you can easily come up with a pretty large list of IP addresses that are in some way tied to your company. Now all you need to do is lookup each IP to see what it’s hosting and who owns it. Easy right?

If you don’t already have a tool for looking up bulk lists of IP addresses or you prefer not to paste a list of your company’s IP addresses into someone else’s website, we’ve got a solution. Whodat.py was written to take very large lists of IP addresses and perform a series of whois and geoip lookups. If the IP address is owned by Amazon or Microsoft, additional details on the service or data center get added based the host’s online documentation. This tool was designed for regular use by our penetration testers, but its concepts and capabilities are a core functionality of our CASM Engine™ and our suite of Continuous Attack Surface Management and Continuous Penetration Testing subscriptions.

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